In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them.
ISBN 978-0-626-20961-2
SANS 10089-1:2008
Edition 4.3
Published by Standards South Africa
1 dr lategan road groenkloof private bag x191 pretoria 0001
tel: 012 428 7911 fax: 012 344 1568 international code + 27 12
www.stansa.co.za
© Standards South Africa
I
Table of changes
Change No. | Date | Scope |
---|---|---|
Amdt 1 | 2003 | Amended to update and add to normative references and the bibliography to align with national and international standards, to add two new definitions and to correct the values given in annex B. |
Amdt 2 | 2007 | Amended to include a statement in the foreword on application of this standard in other jurisdictions, to update and add referenced standards, to update the definition of “acceptable” and references to legislation, to add fixed tanks to table 1, to replace “one fifth” with “one and a half for minimum distance in table 3, and to include information on UL standard publishers in footnote 2. |
Amdt 3 | 2008 | Amended to correct the formula for vertical rate of rise in annex B and to delete withdrawn standards. |
Standards South Africa wishes to acknowledge the valuable assistance derived from publications of the following organizations:
Advisory Fire Management Council
American Petroleum Institute
American Society for Testing and Materials
BP Southern Africa (Pty) Ltd
British Standards Institution
Caltex Oil (SA) (Pty) Ltd
Engen Petroleum Limited
European Petroleum Organizations (European Technical Cooperation)
Institute of Petroleum (UK)
International Oil Tanker Terminal Safety Group
National Fire Protection Association International (USA)
The Associated Octel Company Limited (London)
This South African standard was approved by National Committee StanSA TC 5120.18, The Petroleum industry – Equipment and systems, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement
This document was published in June 2008. This document supersedes SANS 10089-1:2007 (edition 4.2).
A vertical line in the margin shows where the text has been technically modified by amendment No. 3.
This document was written in order to support a specific item of South African regulation and, of necessity, includes references to South African legislation. It therefore might not be suitable for direct application in other jurisdictions where conflicting legislation exists.
Amdt 2
II
SANS 10089 consists of the following parts, under the general title, The petroleum industry.
Annexes A, B, C, D and E are for information only.
Concurrent with the rewriting of this part of SANS 10089, there were far-reaching developments in the marketing of petroleum products. Bulk storage and handling were traditionally handled by the large petroleum companies whose proven integrity in matters of safety and fire engineering have been synonymous with the industry.
Recently, however, there has been a rapid change to the enfranchising of bulk storage, handling and distribution to sales agents who have minimal (if any) experience in or previous exposure to petroleum operations.
During the lifetime of this fourth edition, it can be expected that many more (less qualified) new oil companies will wish to operate, modify, expand or construct distribution facilities. They will have to comply with this part of SANS 10089 and will look to it for guidance.
Nothing prevents any user from opting for a rational design, but any user should be able to use this part of SANS 10089 as a stand-alone code. It draws on the best of previous versions in the South African context and gives guidance with regard to other code systems that could be meaningful in local conditions.
It should be noted that compliance with this part of SANS 10089 does not grant immunity from the relevant legal requirements, including municipal and other by-laws.
Although it is believed that the adoption of this part of SANS 10089 will help reduce the risk of accidents, the South African Bureau of Standards cannot accept any responsibility for any kind of damage or alleged damage in or about premises, areas or vehicles to which this part of SANS 10089 has been applied.
1
Page | |||
Acknowledgement | |||
Foreword | |||
Introduction | 1 | ||
1 | Scope | 5 | |
2 | Normative references | 5 | |
3 | Definitions | 8 | |
4 | Planning of bulk depots | 15 | |
4.1 | Design and construction of bulk storage tanks | 15 | |
4.2 | Topography | 15 | |
4.3 | Boundaries | 16 | |
4.4 | Tankage layout: minimum safety distances | 16 | |
4.5 | Tank farms and bunding | 23 | |
4.6 | Location and spacing of buildings. | 25 | |
4.7 | Roadways | 26 | |
4.8 | Railway sidings | 27 | |
4.9 | Drainage and interceptors. | 28 | |
4.10 | Loading and discharging facilities | 29 | |
5 | Design and construction of plant, equipment and buildings | 29 | |
5.1 | Above-ground tankage | 29 | |
5.2 | Pipelines | 29 | |
5.3 | Hoses (for product) | 31 | |
5.4 | Pumping plant (for product) | 31 | |
5.5 | Loading and unloading of bulk road vehicles and bulk rail vehicles | 32 | |
5.6 | Ship loading and discharging equipment | 33 | |
5.7 | Package filling and packaged-oil warehouse buildings | 33 | |
5.8 | Packed-product storage areas | 34 | |
5.9 | General site works | 34 | |
6 | Operations | 35 | |
6.1 | Receiving bulk cargoes from and delivering bulk cargoes to tank vehicles | 35 | |
6.2 | Loading and unloading of rail tank vehicles | 36 | |
6.3 | Loading and unloading of road vehicles | 36 | |
6.4 | Containers | 37 | |
7 | Fire precautions and fire control in bulk depots | 37 | |
7.1 | General | 37 | |
7.2 | Ignition sources | 37 | |
7.3 | Access control | 37 | |
7.4 | Housekeeping and vegetation | 38 | |
7.5 | Absorbents | 38 | |
7.6 | Work permits | 38 | |
7.7 | Training (safety organization) | 38 | |
7.8 | Scale of fire-fighting equipment | 39 2 | |
7.9 | Location and marking of equipment | 40 | |
7.10 | Fire-fighting equipment | 41 | |
7.11 | Colour identification of fire-fighting equipment | 42 | |
7.12 | Employees for fire-fighting | 42 | |
7.13 | Fire drills | 42 | |
7.14 | Co-operation with the local fire authorities | 43 | |
7.15 | Warning notices and signs | 43 | |
7.16 | Testing and records | 43 | |
8 | Protection and welfare of personnel | 43 | |
8.1 | General | 43 | |
8.2 | Safety and protection measures | 43 | |
9 | Maintenance of and extensions to depots | 44 | |
9.1 | Risk assessment procedure | 44 | |
9.2 | Repairs and alterations | 45 | |
9.3 | Personnel | 46 | |
9.4 | Plant | 46 | |
9.5 | Access to site | 47 | |
9.6 | Temporary fencing | 47 | |
9.7 | Notices | 47 | |
9.8 | Permits | 47 | |
9.9 | Safety | 48 | |
9.10 | Gas-freeing of tanks | 48 | |
9.11 | Cleaning of tanks | 52 | |
10 | Transportation of petroleum products (other than LPG) by road and by rail | 54 | |
11 | Pollution control | 54 | |
Annex A (informative) |
Determination of water requirements for the highest fire risk area | 55 | |
Annex B (informative) |
Design criteria for interceptors (gravity separators) | 68 | |
Annex C (informative) |
Examples of typical work permits | 72 | |
Annex D (informative) |
Safety distances for LPG facilities. | 80 | |
Annex E (informative) |
Bibliography. | 81 |
3
4
The petroleum industry
Part 1:
Storage and distribution of petroleum products in above-ground bulk installations
This part of SANS 10089 covers the layout and design of petroleum bulk depots, and the installation of equipment of the types normally used for the handling, storage and distribution of petroleum products and their derivatives, other than equipment that is used for storage and dispensing on consumer premises (including service stations) and for which relevant standards exist.
A design will meet the requirements of this part of SANS 10089 if it complies with any one of the approved standards listed (see 2.1). However, such a standard shall be applied in its entirety (where applicable). For example, the product classification of one standard cannot be used in combination with the design of another standard.
NOTES
The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of SANS 10089. All documents are subject to revision and, since any reference to a normative document is deemed to be a reference to the latest edition of that document, parties to agreements based on this part of SANS 10089 are encouraged to take steps to ensure the use of the most recent editions of the documents indicated below. Information on currently valid national and international standards can be obtained from Standards South Africa.
API RP 2003, Protection against ignitions arising out of static, lightning, and stray currents.
API Spec 5L, Specification for line pipe.
5
API Std 620, Design and construction of large, welded, low-pressure storage tanks.
API Std 650, Welded steel tanks for oil storage.
API Std 2000, Venting atmospheric and low-pressure storage tanks – Nonrefrigerated and refrigerated.
ASME B31.4, Pipeline transportation systems for liquid hydrocarbons and other liquids.
ASTM D 86, Standard test method for distillation of petroleum products at atmospheric pressure.
EN 1361, Rubber hoses and hose assemblies for aviation fuel handling – Specification.
Amdt 1
EN 1765, Rubber hose assemblies for oil suction and discharge services – Specification for the assemblies.
Amdt 1
EN 14015, Specification for the design and manufacture of site built, vertical, cylindrical, flat-bottomed, above ground, welded, steel tanks for the storage of liquids at ambient temperature and above.
Amdt 2
IP method 341), Determination of closed flash point – Pensky-Martens method.
IP method 1701) Petroleum products – Determination of flash point – Abel closed cup method.
NFPA 11, Standard for low-, medium-, and high-expansion foam systems.
SANS 62-1, Steel pipes – Part 1: Pipes suitable for threading and of nominal size not exceeding 150 mm.
SANS 62-2 (SABS 62-2), Steel pipes – Part 2: Screwed pieces and pipe fittings of nominal size not exceeding 150 mm.
SANS 252, Metallic hose assemblies for liquid petroleum gases and liquefied natural gases.
Amdt 2
SANS 543, Fire hose reels (with semi-rigid hose).
Amdt 1
SANS 1091, National colour standard.
SANS 1128-1 (SABS 1128-1), Fire fighting equipment – Part 1: Components of underground and above-ground hydrant systems.
SANS 1128-2 (SABS 1128-2), Fire fighting equipment – Part 2: Hose couplings, connectors, and branch pipe and nozzle connections.
SANS 1141, Aircraft fuelling hose.
SANS 1142 (SABS 1142), Diesel engines modified for use in hazardous locations (other than in mines).
SANS 1156-1, Hose for liquefied petroleum gas (LPG) – Part 1: Hose used in road and rail transport.
SANS 1186-1, Symbolic safety signs – Part 1: Standard signs and general requirements.
Amdt 1
1) IP test methods are published by the Institute of Petroleum, 61 New Cavendish Street, London W1M8AR, England.
6
SANS 1475-1, The production of reconditioned fire-fighting equipment – Part 1: Portable rechargeable fire extinguishers.
SANS 1518, Transport of dangerous goods – Design requirements for road vehicles and portable tanks.
Amdt 2
SANS 1522, Fire extinguishing powders.
SANS 1910, Portable refillable fire extinguishers.
Amdt 2
SANS 10085-1, The design, erection, use and inspection of access scaffolding – Part 1: Steel access scaffolding.
Amdt 2
SANS 10086-1, The installation, inspection and maintenance of equipment used in explosive atmospheres – Part 1: Installations including surface installations on mines.
SANS 10089-2, The petroleum industry – Part 2: Electrical and other installations in the distribution and marketing sector.
SANS 10108, The classification of hazardous locations and the selection of equipment for use in such locations.
SANS 10114-1, Interior lighting – Part 1: Artificial lighting of interiors.
SANS 10121, Cathodic protection of buried and submerged structures.
SANS 10123 (SABS 0123), The control of undesirable static electricity.
SANS 10140-3, Identification colour markings – Part 3: Contents of pipelines.
SANS 10142-1, The wiring of premises – Part 1: Low-voltage installations.
Amdt 1
SANS 10228, The identification and classification of dangerous goods for transport.
SANS 10229-1, Transport of dangerous goods – Packaging and large packaging for road and rail transport – Part 1: Packaging.
Amdt 2
SANS 10231 Transport of dangerous goods – Operational requirements for road vehicles.
SANS 10232-1, Transport of dangerous goods – Emergency information systems – Part 1: Emergency information system for road transport.
SANS 10233 (SABS 0233), Transportation of dangerous goods – Intermediate bulk containers.
SANS 10263 (SABS 0263), The warehousing of dangerous goods – Enclosed storage areas and covered and uncovered outdoor storage yards.
SANS 10400 (SABS 0400), The application of the National Building Regulations.
IATA Regulations. International Air Transport Association.
IMDG, International maritime dangerous goods code. International Maritime Organization.
International safety guide for oil tankers and terminals. Distributed on behalf of the International Oil Tanker Terminal Safety Group by the Institute of Petroleum (61 New Cavendish St, London W1M8AR).
7
Major hazard installation regulations. Part of the South African Occupational Health and Safety Act, 1993 (Act No. 85 of 1993).
OCTEL Lead alkyl antiknock compounds. The Associated Octel Company Limited (23 Berkeley Square, London W1X6DT).
Spoornet Manual on Dangerous Goods – Requirements concerning the packing, acceptance, transportation and delivery of dangerous goods. Transnet Limited, Johannesburg.
For the purposes of this part of SANS 10089, the following definitions apply:
acceptable to the authority administering this standard, or to the parties concluding the purchase contract, as relevant
Amdt 2
a person registered in terms of regulation 9 of the Occupational Health and Safety Act, 1993 (Act No. 85 of 1993), as an electrical tester for single phase, an installation electrician or a master installation electrician
approved by the appropriate approving authority
explosion-protected equipment that has been submitted to the appropriate approving authority for examination and testing and for which a certificate of approval for a prescribed application has been issued
the appropriate of the following:
the technique of maintaining an atmosphere that is either inert or fuel-enriched in the vapour space of a container or vessel
Amdt 1
8
the temperature at which a liquid exerts a vapour pressure of 101,3 kPa. Where an accurate boiling point is not available for the material in question, or in the case of mixtures that do not have a constant boiling point, for the purposes of this part of SANS 10089, the 10 % point of distillation determined in accordance with ASTM D 86 can be taken as the boiling point of the liquid
an apparatus that allows the wearer to breathe independently of the ambient atmosphere
as defined in the National Building Regulations and Building Standards Act, 1977 (Act No. 103 of 1977), as amended
premises (sometimes referred to as marketing installations or terminals), on which the capacity for the storage of flammable goods or combustible goods (or both) exceeds 200 m3 in above-ground tanks, on which goods are normally received from a refinery or other bulk depot by road, rail, sea or pipeline (or a combination of these), and from which such flammable goods or combustible goods (or both) are delivered
NOTE For above-ground storage of less than 200 m3 for petroleum products, see SANS 10131.
an area bounded by ground contours that confine spillage, or an area surrounded by bund walls
wall
a wall designed to confine product spillage to the bunded area
the class of petroleum product, based on the following classification:
NOTES
If a class II or a class III combustible liquid should be stored or handled at temperatures above its flash point and at or above its boiling point, special precautions should be taken in both the layout and the operation for such a liquid.
an instrument used to measure the concentration of flammable vapours in air, up to the lower explosive limits (for example, an explosimeter)
a liquid that has a closed-cup flash point of 38 °C or above
a person who has the necessary knowledge of and ability with regard to the particular process or type of plant and equipment to which this part of SANS 10089 refers, to render him capable of the work involved
a person designated by his employer in terms of the Occupational Health and Safety Act, 1993 (Act No. 85 of 1993)
residual water or any other liquid resulting from the use of water for industrial purposes, including any substance suspended therein and any storm water flowing or seeping or being pumped from a site, while such a site is in production or after its temporary closure or permanent abandonment
apparatus enclosed in a case that
NOTE The German term “explosiongeschützt” (frequently translated as “explosion-proof") is used to denote apparatus protected by means other than an explosion-proof case. Such other means include those described as “type e apparatus”, “intrinsically safe apparatus” and “pressurized apparatus".
10
a barrier across pipeline trenches to prevent the spread of fire
a wall intended to prevent the spread of fire or the passage of flammable liquids or gases
flame trap
a device used to prevent the passage of flame into or out of an apparatus or equipment
see 3.22.
descriptive of a material that is capable of ignition
NOTES
closed-cup flash point
the lowest temperature at which the application of a small flame causes the vapour above a liquid to ignite when the product is heated under prescribed conditions, in a “closed” container (IP method 34 and IP method 170)
the height of a bund wall above the calculated liquid surface
descriptive of a vessel, a container or an area that contains an atmosphere in which the concentration(s) of flammable gases or toxic gases (or both) have been certified as being within the prescribed safe limits. (See also 9.10.6 and table 5.)
a certificate, issued by a competent person, that certifies that tests have proved that the concentrations of flammable gases or toxic gases (or both) in the relevant atmosphere are within the prescribed limits (see clause C.1)
an area in which flammable gases or vapours are or might be present in the air in quantities sufficient to become hazardous
NOTE Hazardous areas are classified as follows (see also SANS 10089-2 and SANS 60079-10):
an atmosphere that presents a threat to human life because
NOTE The term refers exclusively to danger that arises from ignition, but it should be remembered that a hazardous condition also exists where there is a lack of oxygen or where the atmosphere contains toxic gas or vapour, or an inert gas (such as is sometimes used to purge a tank), in such a concentration as to endanger life.
a technique by which a combustible mixture is rendered non-ignitable by addition of an inert gas or a non-combustible dust (See also 3.6.)
Amdt 1
gravity separator
an approved chamber or chambers included in a drainage system and so designed as to permit the passage of effluent but to retain any hydrocarbons that are not miscible in water and that could be carried by the effluent stream.
NOTE Design details for interceptors are given in annex B.
one or more header pipes, with branch connections, used for collecting or distributing the products carried in pipelines, pumps or vessels
the maximum pressure, steady state or static, that is permitted anywhere in a tank during normal service
mobile equipment
plant (or equipment) that is mounted on its own wheels or on tracks that has other facilities that give it mobility
12
a tank that is above the ground and completely covered by earth, sand or other suitable material
a depot for the storage of one or more grades of flammable or combustible products in packages, i.e. a depot in which no product is stored in above-ground or in semi-buried tanks
a document that is issued by a designated person, or persons, and that permits specific work to be carried out in one or more defined areas
fire protection for structures on property adjacent to a liquid petroleum storage site
NOTE Fire protection for such structures should be approved when the structures are located either within the jurisdiction of any public fire department or adjacent to plants that have private fire services capable of providing cooling water streams on the structures.
an apparatus that allows the wearer to breathe filtered respirable air (See also 3.8.)
NOTE An atmosphere that is not ignitable is not necessarily respirable.
an engineer who is registered in terms of the Engineering Profession Act, 2000 (Act No. 46 of 2000)
a non-corrodible wire gauze, of nominal aperture size not exceeding 0,5 mm, that is used to prevent the passage of flames into or out of an apparatus, equipment or a building
an area around above-ground tanks and around semi-buried tanks that does not necessarily fall within the premises of the company that operates the site, but over which such company can ensure control and enforcement of safety requirements by a legally binding agreement
an atmosphere that is life-supporting, non-toxic and incapable of being ignited (See 9.10.6 and table 5.)
a tank that is partly in the ground and completely covered by earth, sand or other suitable material
any means of supplying sufficient energy to ignite a flammable atmosphere
13
a device that is capable of preventing the emission of incandescent particles from the exhaust systems of internal combustion engines into the atmosphere
NOTE A spark arrestor is not necessarily a flame trap (flame arrestor).
one of the following types of tank, that are commonly used to store liquid petroleum products:
a fixed-roof tank, that has a weak roof-to-shell seam, and that is designed to withstand an internal vapour pressure not exceeding (measured at the top of the tank) 3,5 kPa, and that is generally free-venting. (A tank with a vertical cone roof is a typical example.)
NOTE Atmospheric tanks are not designed for storing a liquid at a temperature at or equal to its boiling point.
a type of tank that can be of two designs:
a tank that is designed to an approved standard (API Std 650 or equivalent), with a pontoon (double-deck metal floating roof) that meets the requirements of the design standard; or
a cone-roof tank with an internal floating roof or a lightweight metal pan, and with roof and eaves ventilation designed in accordance with an approved standard (API Std 650 or equivalent)
a fixed-roof tank, that has a strong roof-to-shell seam, and that is designed to withstand an internal pressure above 3,5 kPa, but not exceeding 103,4 kPa, measured at the top of the tank (A tank with a hemispheroid top is a typical example.)
in regard to railway sidings, only that area on each side of the actual staging length of the rail tank car
an area of which no part is classified as a hazardous area
a liquid that, in the pure state or as commercially produced or transported, will vigorously polymerize, decompose, undergo condensation reaction, or become self-reactive under conditions of shock, pressure or temperature
14
Plans submitted for approval to the approving authority concerned shall be signed by a professional or responsible engineer who thereby certifies that such plans comply with the provisions of this part of SANS 10089. All tanks shall be designed and built in accordance with an approved standard (for example, API Std 650).
An elevated tank shall be so designed that it is supported on a structure with a 4 h fire rating.
A vertical tank shall consist of not more than one compartment.
Hydrocarbons are volatile under certain conditions and their vapours in specific concentrations are flammable. Precautions shall be taken to prevent their ignition and, in the event of fire, to prevent further spread. One facet of a total fire protection package is to reduce the likelihood of a fire by siting facilities at what is considered to be a safe distance from one another. Safety distances do not guarantee protection from fire hazard, but they help to prevent the start of a fire by ensuring that any flammable vapour generated by one facility will diffuse to a concentration well below the lower explosive level (LEL) before it reaches any other facility or area where a source of ignition might exist.
The siting of a bulk depot is of paramount importance, not only from a marketing point of view but also from a fire and security point of view. Cognizance shall be taken of the following:
To facilitate future monitoring of the environment, the above information shall be obtained and recorded before construction commences. (See also the Major Hazard Installation Regulations of the OHS Act.)
In the interests of security, the depot shall be so enclosed as to prevent unauthorized access (see also 5.9.5).
Safety distances of tanks from each other or from property boundaries, public roads, third-party properties, safe areas and other facilities in the depot shall be based on either of two criteria:
The safety distances given in 4.4.2 are the consequent minima that are regarded as necessary.
NOTE Annex D gives typical safety distances for an LPG installation.
The minimum shell-to-shell spacing for horizontal tanks that contain class I, II or IIIA liquids shall be as given in columns 3 and 4 of table 1. The minimum for shell-to-shell spacing for vertical floating roof tanks that contain class I, II or IIIA liquids shall be as given in column 2.
16
1 | 2 | 3 | 4 |
---|---|---|---|
Impounding (see 4.5) |
Floating-roof tanks | Fixed or horizontal tanks | |
Class I or II liquids | Class IIIA liquids | ||
Tanks of diameter not exceeding 45 m | |||
Remote or in the tank bund |
One-sixth of the sum of adjacent tank diameters but not less than 1 m |
One-sixth of the sum of adjacent tank diameters but not less than 1 m |
One-sixth of the sum of adjacent tank diameters but not less than 1 m |
Tanks of diameter exceeding 45 m | |||
In the tank bund | One-quarter of the sum of adjacent tank diameters |
One-third of the sum of adjacent tank diameters |
One-quarter of the sum of adjacent tank diameters |
Remote | One-sixth of the sum of adjacent tank diameters |
One-quarter of the sum of adjacent tank diameters |
One-sixth of the sum of adjacent tank diameters |
Amdt 2
In the case of tanks that contain a stable liquid of class I, II or IIIA, at an operating pressure of 17,2 kPa or less, the minimum distance between the tank and any property boundary, public road or building shall be as given in table 2.
17
1 | 2 | 3 | 4 |
---|---|---|---|
Type of tank | Level of protection | Minimum distance from boundary of a property that is or can be built on, including the far side of a public road, but not less than 2 m |
Minimum distance from the near side of a public road, or nearest important building on the same property, but not less than 2 m |
Floating-roof (all types) | Protection in case of exposure | Half of the diameter of the tank | One-sixth of the diameter of the tank |
None | Diameter of the tank, but need not exceed 53 m | One-sixth of the diameter of the tank | |
Vertical with weak roof-to-shell seam | Tanks of diameter 45 m or less, with approved foam or inerting systems |
Half of the diameter of the tank | One-sixth of the diameter of the tank |
Protection in case of exposure | Diameter of the tank | One-third of the diameter of the tank | |
None | Double the diameter of the tank but need not exceed 106 m | One-third of the diameter of the tank | |
Horizontal or vertical with emergency relief venting to limit pressure to 17,2 kPa |
Approved inerting system on the tank or approved foam system on vertical tanks |
Half the values given in column 2 of table 4 | Half the values given in column 3 of table 4 |
Protection in case of exposure | Value given in column 2 of table 4 | Value given in column 3 of table 4 | |
None | Double the value given in column 2 of table 4 | Value given in column 3 of table 4 |
In the case of tanks that contain a stable liquid of class I, II or IIIA, at an operating pressure exceeding 17,2 kPa, the minimum distance between the tank and any property boundary, public road or building shall be as given in table 3.
1 | 2 | 3 | 4 |
---|---|---|---|
Type of tank | Level of protection | Minimum distance from boundary of a property that is or can be built on, including the far side of a public road |
Minimum distance from the near side of a public road, or nearest important building on the same property |
Any type | Protection in case of exposure | One and a half of the values given in column 2 of table 4 but not less than 7,5 m |
One and a half of the values given in column 3 of table 4, but not less than 7,5 m |
None | Three times the values given, in column 2 of table 4, but not, less than 15 m |
One and a half of the values, given in column 3 of table 4, but not less than 7,5 m |
Amdt 2
18
1 | 2 | 3 |
---|---|---|
Tank capacity | Minimum distance from boundary of a property that is or can be built on, including the far side of a public road | Minimum distance from the near side of a public road, or from the nearest important building on the same property |
m3 | m | m |
Less than one | 1,5 | 1,5 |
1,0 – 2,2 | 3,0 | 1,5 |
2,201 – 45,0 | 4,5 | 1,5 |
45,001 – 82,0 | 6,0 | 1,5 |
82,001 – 200,0 | 9,0 | 3,0 |
200,001 – 378,0 | 15,0 | 4,5 |
378,001 – 1 892,5 | 25,0 | 7,6 |
1 892,501 – 3 785,0 | 30,5 | 11,0 |
3 785,001 – 7 570,0 | 41,0 | 13,7 |
7 570,001 – 11 355,0 | 50,0 | 17,0 |
11 355,001 or more | 53,0 | 18,0 |
In the case of tanks that contain a class IIIB liquid, the minimum distance between the tank and any property boundary, public road or building shall be as given in table 5.
1 | 2 | 3 |
---|---|---|
Tank capacity | Minimum distance from boundary of a property, that is or can be built on, including the far side of a public road |
Minimum distance from near side of a public road, combustible structure or important building on the same property |
m3 | m | m |
Less than one or equal to 48 |
1,5 | 1,5 |
> 48 – 112 | 3,0 | 1,5 |
> 112 – 192 | 3,0 | 3,0 |
> 192 – 384 | 4,5 | 3,0 |
> 384 | 4,5 | 4,5 |
The minimum distance between a tank and the toe of the inside of a bund wall shall be at least 1,5 m.
19
Figure 1 — Typical bulk storage installation showing safety distances
20
Figure 1 (concluded)
Tankage: Class I, II and IIIA liquids | |||
---|---|---|---|
Dimensions | Level of protection | ||
A1 A2 |
1/2 diameter of tank 1 × diameter of tank 1/6 diameter of tank |
Protection in case of exposure None Protection in case of exposure |
|
B1 B2 |
1/2 diameter of tank 1 × diameter of tank 2 × diameter of tank 1/6 diameter of tank 1/3 diameter of tank |
Approved foam or inerting system Protection in case of exposure None Approved foam or inerting system Protection in case of exposure |
|
C1 C2 |
1/2 of values given in column 2 of table 4 Table 3 2 × values in column 2 of table 4 1/2 of values in column 2 of table 4 Table 3 |
Approved inerting system on the tank, or approved foam system on vertical tanks Protection in case of exposure None Approved inerting system on the tank, or approved foam system on vertical tanks Protection in case of exposure |
|
NOTES 1 Applies only to tanks that are less than 45 m in diameter and that operate at pressures of less than 17,2 kPa, in the case of stable liquids. In the case of tanks that operate at pressures exceeding 17,2 kPa, see table 3. 2 The minimum distance between a tank and the toe of a bund wall shall be 1,5 m, and that between a bund wall and a property boundary shall be 3 m. 3 The minimum spacing between tanks shall be at least 1 m. |
|||
Tankage: Class IIIB liquids | |||
NOTES 1 In the case of class IIIB liquids, see table 5. 2 The minimum distance between tanks shall be at least 1 m. 3 The minimum distance between a tank and the toe of a bund wall shall be 1,5 m, and that between a bund wall and a property boundary shall be 3 m. |
|||
General safety distances | |||
Dimensions | Classification | Description | |
D | 15 m 6 m 6 m 3 m |
Class I Class I Class II Class II Class IIIA |
If boundary is open-type fencing If boundary is a solid wall If boundary is open-type fencing If boundary is a solid wall No restriction |
E | 15 m 6 m |
Class I Classes II and IIIA |
|
F | 15 m | Classes I, II and IIIA |
21
All atmospheric storage tanks shall be adequately vented to prevent, in the case of a cone-roof tank, the development of a vacuum or pressure that could distort the roof, or in the case of other atmospheric tanks, the design pressure from being exceeded as a result of filling, emptying, and temperature changes. Protection shall be provided to prevent the overpressure in any pump from being discharged into the tank or vessel where the pump discharge pressure can exceed the design pressure of the tank.
Normal vents shall comply with the requirements of an approved standard, such as API Std 2000, or another acceptable standard, and shall be of size at least the same as that of the filling or withdrawal connection (whichever is the larger), but in no case shall the nominal inside diameter be less than 30 mm.
In the case of a tank or pressure vessel that has more than one fill or withdrawal connection, and where simultaneous filling and withdrawal can take place, the vent size shall be based on the maximum anticipated simultaneous flow.
The outlets of all vents and vent drains on tanks that are equipped with venting to permit pressures from exceeding 17,2 kPa shall be arranged to discharge in such a way as to prevent localized overheating of, or flame impingement on any part of the tank, should vapours from such vents ignite.
Tanks and pressure vessels for storing class I liquids could be equipped with venting devices that are normally closed except when venting to pressure or vacuum conditions. Tanks and pressure vessels for storing class IA, IB and IC liquids shall be equipped with venting devices that are normally closed except when venting under pressure or vacuum conditions, or with listed flame arrestors. Tanks for storing class I liquids equipped with blankets shall be free venting.
Tanks for storing class II or class III petroleum products could be fitted with open vents.
Pressure and vacuum vents or open vents should not be fitted with fine mesh gauze (less than 6 mm) that is liable to become clogged with dust, dirt or ice and impair venting capacity. However, where such vents are equipped with screens to prevent the entry of foreign matter, the screen shall be of aperture size at least 6 mm.
Every above-ground tank shall have some form of approved emergency venting that will relieve excessive internal pressure in the event of exposure to fire.
In the case of vertical tanks, emergency venting could be provided by a floating roof or, if the tank has a fixed roof, by a weak roof-to-shell seam that will fail before any other seam or plate of the tank shell or bottom.
22
If emergency venting is provided by means of pressure relieving vents, the venting capacity of normal vents together with emergency vents should be sufficient to prevent failure of, in the case of a vertical tank, the shell or bottom or, in the case of a horizontal tank, of the shell or ends.
The emergency venting capacity provided shall be in accordance with an approved standard, such as API Std 2000.
Spillages and fires that involve bulk storage tanks could pose a risk to the depot, adjoining property, the community and the environment. The general purpose of tank farms and bunding is to limit, contain, divert, minimize and manage the impact of spillages and fires.
The design should consider the optimization of tank farm and bunding sizes in conjunction with fire-fighting requirements of the tank farm and its limitations. The design should also consider the risk of pollution to surface and ground water, soil and environment.
NOTE In certain situations, the equipment required to extinguish a fire cannot be justified by the economic consequences of the fire alone. If, by allowing the fire to burn, the risk to people, the environment and property lying outside the restricted area is not increased, the approving authority need not consider the capability to extinguish a fire to be a requirement.
Spillage control can be provided by remote impounding, impounding around tanks, bunding or by a combination of all three.
In both types of impounding, the impoundment area shall be protected by adequately designed systems to prevent the contamination of ground water if such a risk exists.
Where protection of adjoining property and waterways is by means of impounding by building bund walls around tanks, such bunding shall comply with the following:
In the case of tanks that contain liquids of class I, II or III, and that are situated in porous soils, bunded areas shall receive special treatment to prevent the seepage of spilled hazardous liquids to low-lying areas or waterways. (See also 4.9 and 5.9.)
23NOTES
NOTES
Where protection of adjoining property or waterways is by means of drainage to a remote impounding area, such systems shall comply with the following:
Bund walls are not required around packed-product storage areas, storage buildings, filling sheds or pump slabs. Spillage control shall be provided where product is decanted or pumped.
The floors of packed-product facilities shall not be sunken, since petroleum vapours are difficult to clear from such locations and can accumulate and cause toxic and fire hazards.
To facilitate night operations, tank farms shall be provided with adequate artificial lighting facilities that comply with the recommendations given in SANS 10089-2 and SANS 10114-1.
All buildings shall comply with the National Building Regulations as contained in SANS 10400.
Where possible, administrative buildings should be located in a safe area (preferably near the main gates), with access from the roadway so that visitors to the offices do not have to enter the working area of the depot. The walls of these buildings may form part of the outer boundary of the depot.
Operational buildings (such as filling sheds and pump slabs) shall be spaced as follows:
In the case of filling sheds for class II petroleum products, the above distances could be reduced to 6 m and 3 m respectively. In the case of class III liquids, no limit need be imposed.
NOTE If the safety distances given in (a) or (b) above cannot be attained, fire walls may be used, subject to approval by the appropriate approving authority.
25
Service buildings do not constitute an inherent petroleum-fire hazard but might include open fires or other similar fire hazards. Service buildings shall be sited in safe areas away from places where products are stored and handled and out of the line of possible vapour travel (at least 15 m away in the case of class I products and at least 6 m away in the case of class II products).
These buildings shall be so located (in safe areas) that their equipment can be safely operated in the event of a fire.
The walls of buildings other than buildings for which safety distances are given in 4.6.2, may form part of the boundary of a depot. Any openings in such walls shall have some suitable form of security.
On-site roads shall not be used for parking. Special parking areas shall be allocated for petroleum-carrying vehicles. Parking areas for bulk tankers shall be so designed that a large spill will not endanger the tank farm, buildings or any other structures. If possible, allocate a parking area for private cars, preferably on a part of the site that is remote and separated from operational areas.
Vehicles (other than those normally employed on the premises) shall not be used on on-site roads without the prior approval of the manager or his authorized representative. Suitable lighting is essential for night operations. (See also SANS 10089-2 and SANS 10114-1.)
Where pipelines or cables are routed adjacent to roads, protective kerbing shall be provided. If kerbing cannot be provided, warning posts or fencing shall be provided to prevent accidental damage.
Symbolic safety signs and warning signs shall be provided where necessary. In large depots, the numbering or naming of roads is desirable.
The effectiveness with which fire-fighting equipment can be used, particularly in the early stages of a petroleum-product fire, depends primarily on the speed with which such equipment can be brought into active use. (See also clause 7.)
The layout of a depot should embody roadways or all-weather hard-surfaced tracks that give mobile equipment and persons access to hydrants and permit effective and safe use of the equipment, irrespective of the location of the outbreak of the fire or the direction of the wind. All such roads and tracks, exits and entrances to buildings, and access to fire-fighting equipment shall be unobstructed.
Hydrants and fire-fighting equipment shall be so located that they can be approached from different directions, and distinctly marked that they can be easily seen (reflective material is recommended to facilitate visibility at night). Hydrants shall be provided at positions that would enable any fire to be combated, irrespective of the wind direction.
26
When the layout of a bulk storage depot is being planned,
NOTE Subsidiary roads may be of single-track width with adequate passing bays, and a lower standard of surfacing and drainage is acceptable.
The provision and construction of private sidings shall be in accordance with the relevant regulations of Spoornet. (See 4.10.1 and the Spoornet manual on dangerous goods (see 2.2).) Sidings shall be so sited that they cannot be cut off by a fire in another area and that they are accessible for fire-fighting purposes.
The position of the railway track relative to plant and to loading gantries of platforms shall be in accordance with the regulations of Spoornet.
Loading sidings shall be located at least 15 m from the running line used by locomotives (electric or other), and rail tank vehicle staging points shall be located at least 15 m from tank shells, buildings in which work that involves heat is done, important buildings (for example, offices), bulk truck loading racks that handle class I products, package warehouses and filling sheds that contain class I products, and possible fire areas. In the case of package warehouses, filling sheds and bulk loading racks that handle class II and III products only, this distance may be reduced to 6 m (see 4.6 and figure 1).
27
Drainage shall be planned in accordance with statutory regulations. Every advantage of natural seepage for disposal of surface water shall be utilized. Existing storm-water drains, rivers and streams shall be used to cope with the outflow, although it might be necessary to provide special catchment basins or seepage areas in large plants where heavy precipitation rates (that might temporarily be beyond the capacity of the local system) can be expected.
Suitable drainage facilities shall be provided to deal with surface water and to dispose of fire-fighting water. The water used to control a fire shall be of an acceptable quality (free from hydrocarbons, solvents, alcohols and any additives) before the water is passed into drains.
Outlets from tank farm areas shall be controlled by means of valves situated outside the bunded areas, because access to these valves might be needed during fire-fighting to release excess cooling water.
The valves shall be kept locked in the closed position at all times unless drainage is taking place under the control of a designated person. The valves shall be clearly identified and marked with the direction of opening.
Where it is necessary to use interceptors to separate contaminants from water, consult the relevant regulations as contained in the National Water Act, 1998, as amended. The local authority by-laws shall be consulted and the collecting system shall be so designed as to minimize the amount of surface water that results from precipitation and normal drainage and that has to be routed through the interceptors (thus avoiding the need for inordinately large interceptors). This is best achieved by providing, where possible, separate systems for surface water and for water from contaminated sources such as tank farms and loading and filling areas. (For design details of an interceptor, see annex B.)
Where a local system for the disposal of sewage exists, it is obviously desirable that the drainage system be connected to it, but where this is impracticable, septic tanks or other suitable disposal units should be installed. Consult the regulations of the local authority and investigate the suitability of the ground with a view to the installation of disposal beds. Contamination with product in such systems shall be avoided. Conversely, sewage systems shall not be connected to interceptors. (See also the relevant regulations as contained in the National Water Act, 1998, as amended, and the local authority by-laws.)
All wash-bays shall be so designed that effluent, detergents and contaminated water are contained. Run-off water that contains effluent shall be of such quality that it complies with the relevant regulations of the Department of Water Affairs and with the by-laws of the local authority before the water passes into the relevant drains. Specially designed wetlands can also be considered for this purpose.
28
In planning the layout of road and rail facilities, safety, the environment and efficiency shall be regarded as the basic considerations. The location of these facilities will be determined by the topography and by the proximity of risks from outside the property.
All access ladders and operating platforms to facilitate the handling of hoses, the dipping of tanks and the manipulation of valves shall comply with the OHS Act, 1993.
Because of the various types of above-ground tankage that can be constructed, close consideration (based on sound engineering principles and common sense, but within the framework of an approved standard (for example, EN 14015, API Std 620, API Std 650, or equivalent)), shall be given to tankage, especially with regard to foundations, venting (see API Std 2000), earthing (see SANS 10089-2), pipe connections, manholes, stairways, ladders, handrails, gauging equipment, floating roofs, diaphragm roofs, cathodic protection systems and maintenance facilities. (See also the current regulations framed under the OHS Act, 1993, with regard to statutory requirements for earthing, stairways, gangways and ladders.)
Amdt 2
All new vertical tanks shall consist of not more than one compartment and shall incorporate a system that will give early warning of a floor-plate leak.
Elevated tanks shall be supported on structures with a fire rating of at least 4 h.
Underground water mains need not be constructed of steel but shall be designed to withstand a minimum test pressure of 1,5 times the working pressure.
All pipes, valves and pipe fittings used shall have been fabricated to an approved code (or equivalent) (see SANS 62-1 and SANS 62-2, ASME B31.4, or API Spec 5L), and shall have a safety factor that is adequate for the conditions of service.
Inside bunded areas, only valves that are of steel, are fire safe, and that comply with an approved standard shall be used (see also 5.2.1). Elsewhere in the depot, approved cast-iron valves may be used.
Valves shall be designed with a suitable factor of safety relative to the pressures and stresses likely to be met in service, and glands shall be such that they can be repacked without the removal of the valves from service.
Valves of other than the rising spindle type shall incorporate an indicator that shows clearly when they are in the open and the closed positions. Valves used in locations where frost damage can be
29
expected, should be provided with means for draining valve bodies or shall be constructed of mild steel.
Where unidirectional fire-safe valves are installed, they shall be so installed that the contents of the tank are held back.
Pipelines over pathways, roadways and platforms shall be supported by gantries, bridges or other approved structures. Provision shall be made to ensure that personnel do not come into contact with hot product lines and steam lines.
In areas where frost is likely to occur, measures to prevent the freezing of water in pipelines shall be provided in the design of the pipelines. Such measures include draining points in pipelines where water could accumulate, insulation of the line or anti-freeze systems.
Where vehicular traffic could damage pipelines, provision shall be made to protect such pipelines (by means of guardrails, safety barriers or other suitable means).
Drains designed and intended for storm water control or effluent control (or both) shall not be used to house pipelines.
At positions where buried pipelines pass under railways and roadways, and at other points at which heavy loads might be experienced, the pipelines shall be protected from uneven ground settlement. (See also 7.8.5.)
If it is impossible to mark, at ground level, the direct route of a buried pipeline, drawings that give all the important details shall be kept.
NOTE The below-ground installation of product lines should be avoided.
Where pipelines are run in open trenches, the trenches should be either self-draining, or should have fire-stops installed at suitable intervals.
Where necessary, the outer surfaces of above-ground pipelines shall be protected by a suitable coating. All below-ground pipelines shall be protected in an acceptable way with suitable corrosion-resistant materials. If a cathodic protection system is used, it shall comply with SANS 10121.
A cathodic protection system shall
Colour markings or other acceptable means shall be used to identify the product or service for which pipelines and valves are intended (see SANS 10140-3) and the relevant oil-marketing company’s colour coding of product pipework). It is recommended that the lines be stencilled at strategic points, for example, FRESH WATER MAIN, SALT WATER MAIN, FOAM, BASE INJECTION, etc. Letters that are clearly legible and of contrasting colour to the colour coding of the pipeline itself shall be used.
30
Before each completed pipeline is commissioned and, where applicable, before the closing of the trench(es) in which a product pipeline is laid, ensure that the pipeline is properly fabricated and free from leaks by testing it in accordance with the design code employed. It is recommended that all buried pipelines be pressure-tested annually throughout their service life, and provision should be made for this. Pipelines shall be fitted with adequate vent connections, drain connections and fittings to facilitate testing.
Thermal pressure relief shall be provided on all product pipelines.
Pipeline systems shall be so designed, through use of L-port, T-port and non-return valves, that the possibility of flow in unintended directions is minimized.
Hoses shall be used that comply with the requirements of EN 1361, EN 1765, SANS 252, SANS 1141 or SANS 1156-1 (as relevant), or with an equivalent approved specification, and that are designed for a working pressure at least equal to the maximum working pressure likely to be met in the pipeline system to which the hoses might be connected.
Amdt 2
Materials used for the outer covering of hoses shall be resistant to abrasion and to deterioration arising from contact with petroleum products. Hoses shall be pressure-tested at least once a year at a test pressure of 1,5 times the maximum working pressure, and records of such pressure tests shall be kept and made available for inspections.
All pumps for application and intended service in the petroleum industry shall be designed to an approved standard.
The type of pump to be used will be determined by the product characteristics and pumping requirements. Preferably use centrifugal pumps of single-stage or multi-stage design for all products except viscous fuel oils. Where positive-displacement pumps can have significant advantages, they may be used. Screw pumps and piston-type pumps are particularly suitable for handling heavy, heated products. Pumps shall be adequately supported. Spill containment shall be provided for all pumps, and shall include suitable drainage.
Pipe manifolds and pumps shall be protected in an acceptable way from stress induced by the expansion and contraction of pipe lines. Hose connections from manifolds are regarded as a fire risk and shall not be used indiscriminately. Pumps and pump manifolds should preferably not be located inside a bunded area where class I liquids are stored or pumped.
Electric motors that are used to drive pumps shall be rated for continuous operation at the maximum power output likely to be required in service. Electric motors and associated equipment located within a hazardous area shall conform to, and be installed in accordance with, the requirements of SANS 10086-1, SANS 10089-2, SANS 10108 and SANS 10142-1.
31
Arrangements for either open or closed loading can be adopted to prevent splash loading. Where top loading arrangements are used, the point of discharge from the loading arm shall be positioned close to the bottom of the tank.
Where bottom loading arrangements are used, an overfill protection method shall be installed to provide control of the quantity delivered to vehicle tanks. (See also the Spoornet manual on dangerous goods (see 2.2)).
In the layout of road-vehicle loading facilities and rail tank-vehicle loading facilities that handle class I (or class I combined with class II and class III) products, the safety distance shall be at least 15 m. If only class II and class III products are handled, this distance may be reduced to 6 m. (See also 4.8.)
Allow for ease of vehicle access and exit, preferably without the need for reversing. It is preferable to group road-vehicle loading points on islands that are parallel to one another. Such islands shall have suitable protection for the loading equipment.
The area adjacent to a railway siding where petroleum products are loaded or unloaded shall be so graded that a major product spillage will be contained.
Where practicable, adequate earth dikes, channels, etc., to control such a spillage shall be provided. Rail-vehicle loading points shall be located alongside the track at intervals that suit the vehicle dimensions.
Wherever possible, the section of track that serves the rail-vehicle loading facilities shall be reserved for this purpose only. The track and pipelines shall be properly bonded and earthed in accordance with the relevant regulations of Spoornet. (See the Spoornet manual on dangerous goods (see 2.2)).
The loading areas shall be surfaced with materials that are resistant to damage by the product(s) and by fire. The surface shall be so graded that spillage occurring at any one point will not flow under vehicles at any other point. An acceptable method of spillage control shall be provided at all filling points, including spillage containment with sufficient capacity to hold a minimum of two minutes’ flow from the loading point with the largest capacity. The drainage system that is used shall be so connected that it drains the area to an interceptor.
These areas shall have permeation values of less than 10–6 cm/s. Any spillage that occurs, shall be contained and passed through an interceptor for recovery.
At loading facilities, spillage containment shall be provided, with sufficient capacity to hold a minimum of two minutes’ flow from the loading point with the largest capacity. At unloading facilities, spillage containment shall be provided to hold the capacity of the single largest rail vehicle that can be accommodated at the siding.
32
Loading equipment can be located at ground level or on a platform of a height that suits the transport fleet. Loading equipment shall be so installed that the strain on any metering unit does not exceed the design limit of the unit.
When automatic loading equipment is used, a manually operated shut-off valve for use in an emergency shall be provided away from the risk area.
Where gravity loading methods are used and also where gravity flow to the equipment is possible, each supply line shall be fitted to the loading points with a quick-acting emergency stop-valve located at a safe distance from the loading area.
All platforms shall comply with the requirements of the OHS Act, 1993.
Materials that are of adequate strength and that are non-combustible shall be used in the construction of loading structures.
Before any connections are made to trucks or rail vehicles and before any flow of the product commences, an electrically continuous path (bond) shall be in place.
The accumulation of static electricity shall be reduced by earthing and bonding the loading or the unloading equipment (or both) in accordance with the recommendations given in SANS 10089-2. (See also SANS 10123.)
All lighting shall comply with the requirements of the OHS Act, 1993. Electrical installations shall be in accordance with the recommendations given in SANS 10089-2.
Ship loading and discharging facilities shall be designed in accordance with the relevant regulations of Spoornet, Portnet and Petronet and the recommendations given in the International safety guide for oil tankers and terminals (see 2.2). (See also 6.1.)
All buildings shall comply with SANS 10400. Use fire-resistant materials in the construction of buildings and equipment. (See also SANS 10263.)
Separator facilities shall be provided to contain any possible spillage and to prevent the spillage from leaking into sewage drains. (See also annex B.)
33
All ventilation in buildings shall comply with the requirements of the OHS Act, 1993. Unless the buildings have open sides, they shall have ventilation openings in opposite sides near the floor and near the roof. (See also SANS 10400 and SANS 10263.)
Where so required by the National Building Regulations (see SANS 10400), alternative means of escape in the event of a fire shall be specified.
Packed-product storage areas shall be provided with suitable drainage and measures against flooding. The base of these storage areas shall be constructed from any suitable material that will provide support for the loads to be carried (including those imposed by any mechanical handling equipment to be used). (See also SANS 10263.)
Bund walls shall be constructed of earth or concrete, and shall be liquid-tight. Bunds shall not be covered with any material that will deteriorate under the effects of any petroleum product. All bunds shall be designed by a person qualified in terms of the Engineering Profession Act, 2000 (Act No. 46 of 2000).
Because of the behaviour of other materials in the event of a fire, earthen bund walls or earthen bund walls contained within masonry are preferred. Ensure that earthen bund walls have a flat crown of at least 0,6 m wide and suitable foundations that prevent oil from seeping underneath them and polluting the environment, or from escaping from the bund. If the earth is permeable, and a high risk of contamination of ground water exists, an approved method of sealing shall be provided (e.g. high density poly-ethelene (HDPE) plastic sheeting).
Whenever a bund wall has been breached, the gap shall be made good as soon as possible, and not left open overnight while any tank it encloses has product in it. Pipelines that pass through bund walls shall be wrapped to protect them from corrosion and sealed to prevent leakage of product.
Main bund walls shall be strong enough to withstand the hydrostatic pressure to which they will be subjected if the space within the bund is filled with water. Cognizance shall be taken of the effect of heat exposure under fire conditions.
Permeable bund floors shall be restricted to a coefficient of permeability not exceeding 10–6 cm/s (in situ).
Railway sidings shall be constructed, operated and maintained in terms of the private siding regulations of Spoornet. Gates equipped with efficient catches to hold them open when required, shall be provided across railway lines. Prevent gates and fences from picking up electric charges from the rails by so constructing the gates that they cannot touch either running rails or check rails.
Electrical installations and earthing arrangements and provisions for the electrical isolation of private sidings from main-line electrified services shall conform to the regulations of Spoornet. No overhead cable shall cross a siding where rail vehicles are loaded or unloaded.
34
The working area, if it has an impermeable surface, shall have surface drainage on each side of the track or, alternatively, filter drains shall be installed to act as collectors. The drains shall be led to an interceptor via a valved system. Adequate means and procedures for catching and disposing of product from leaks and spills shall be provided.
Drainage interceptors shall be provided on all drainage systems where a spillage could occur. Drainage interceptors shall comply with the requirements of 4.9. For design criteria of an interceptor, see annex B.
Boundary fencing with a total vertical height (from ground level to the top of the fence line, including barbed wire) of at least 2,5 m is required. It shall be of an approved type of unclimbable fencing or walling, and may be of chain-link fencing, steel paling, brick or mass concrete walling, or of the slab-and-post concrete type. It will often be found that more than one type of boundary fencing can be usefully employed at the same depot, for example, chain-link or other open-type fencing for tank compounds, and brick or concrete walling for busy operational areas, particularly where these adjoin a public thoroughfare.
NOTE Where a number of bulk depots that belong to different companies adjoin or are situated within a controlled and fenced area such as a dock, the above stipulations may be relaxed, subject to agreement by the approving authority.
Operating procedures shall comply with the relevant procedures of the General Safety Regulations provided for in the OHS Act, 1993.
Throughout each unloading or loading operation, a designated person shall be on duty at the depot and a responsible ship’s officer shall be in attendance. Frequent inspection of ship-to-shore hoses and pressure gauges by a person on duty is necessary in order to detect any possible hose leakage.
All regulations contained in the International safety guide for oil tankers and terminals, and those of Portnet, the fire authorities, the operating company and the OHS Act, 1993, shall be strictly adhered to. It is recommended that an extract of relevant port and depot regulations be handed to the master of a vessel on arrival.
An efficient communication system shall be set up between all persons involved in operations, to ensure that cargo-handling operations are safe and efficient, and that immediate action can be taken in the event of an emergency. Where class I and class II products are handled, communication equipment shall be acceptable explosion-proof equipment, and shall comply with the requirements of SANS 10108.
35
All earthing, bonding and insulation shall comply with the requirements as laid down in SANS 10086-1 and SANS 10089-2 and in the Spoornet manual on dangerous goods (see 2.2).
It is recommended that the entry of rail tank vehicles into a siding and the loading and unloading operations be controlled by a designated person, who shall adhere to the relevant Spoornet regulations contained in the Spoornet manual on dangerous goods (see 2.2). In addition, the following shall be noted:
The following general safety rules shall apply during loading and unloading of road vehicles:
Containers used in the petroleum industry vary considerably in type and size. In order to select the type of pack that will be acceptable, it is necessary to consult the OHS Act, 1993, and the publications of the appropriate transportation authority. The publications available at present are:
However, the publications listed above do not always give details of the components of the pack or of its minimum performance level and, in such cases, containers and packs that comply with the requirements of SANS 10229-1 and SANS 10233 (as relevant) shall be used.
Amdt 2
The protection facilities against fire hazards in bulk depots shall be achieved by good engineering design and construction standards. Safe operational procedures and efficient plant and equipment maintenance shall be such that it is highly improbable that fire will break out.
Any device or action that could cause a flame or spark shall not be permitted in restricted areas, unless authorized by an appropriate permit, the stipulations of which shall be strictly adhered to. (See also 7.2.3.)
Sources of ignition include but are not limited to the following:
cutting and welding, electrical sparks, frictional heat or sparks, furnaces, heating equipment, hot surfaces, lightning, open flames, ovens, radiant heat, smoking, static electricity, stray currents and spontaneous ignition.
Welding, cutting and similar spark-producing operations shall not be permitted within the depot premises without an authorized hot-work permit (see 9.1.2 and 9.8).
All points of entry to depots shall be so planned that persons or passenger vehicles that enter or leave the depot can be observed. Unauthorized persons shall not be permitted access to the depots.
37
Locomotives shall not be permitted to enter hazardous areas, unless they comply with SANS 1142.
Trucks shall not be shunted onto or off sidings during loading and unloading operations. Warning notices (see 7.15) against such shunting shall be displayed near the entrances to sidings during loading or unloading operations.
Fly shunting shall be prohibited.
The site shall be kept free from obstructions and combustible rubbish. Vegetation that is liable to dry out and become a fire hazard shall be kept short and cuttings shall be removed.
Absorbents are basically recommended for containing spillages. Adequate supplies of absorbents shall be available at all times.
Before any construction, repair, or maintenance work is carried out, the appropriate certificates or work permits (or both) shall be issued in terms of 9.8. (For examples, see annex C.)
Each facility shall have a safety organization the size of which will depend upon the complexity of the operation.
The safety organization shall advise the management on the technical and legal aspects of safety and shall provide a programme for the improvement of safety performance (training programmes).
As many persons as practicable at each work site shall be given training in the use of the appropriate fire-fighting equipment. All actions shall comply with the relevant section of the OHS Act, 1993.
Safety training shall include operational procedures, emergency procedures and safe working practices, information on specific hazards, first aid and fire-fighting, and the proper use of protective equipment such as breathing apparatus. Periodic refresher training shall be maintained.
Emergency plans shall be prepared to cover foreseeable types of emergencies, which shall cover situations that range from a small incident to one of disaster proportions where considerable assistance from outside organizations is needed. Any emergency plan shall comply with the regulations for major hazard installations as laid down in the OHS Act, 1993.
38
Water requirements shall be calculated on the basis of a full risk assessment, which shall be conducted by the responsible engineer (see 3.41).
Water supplies shall be sufficient for supplying all the devices that could be used simultaneously for the specified time. This includes not only the volume required for foam apparatus, but also water that could be used for other fire-fighting operations, in addition to normal plant requirements. (See annex A.)
The total supply of water for fire-fighting shall be sufficient to supply water at the rate calculated under 7.8.1 for a period of at least 1 h on any approved rational fire-fighting design. When water requirements are being calculated, allowance shall be made for additional water supplies, for example water needed to cool adjacent tanks, etc.
Water shall at all times be supplied to the most remote site location at a running pressure of 1 MPa (10 bar) at the design flow rate.
Suitable fire pump connections shall be provided to facilitate the pressurization of the water reticulation system in order to comply with 7.8.3. All pump connections (electrical or mechanical) shall be compatible with fire-fighting equipment used by the local authorities.
Wherever practical, the hydrant main shall be buried to withstand the vehicular traffic (for example, fire tenders). Suitable risers, spaced not more than 90 m apart, sufficient hydrant outlets, and hose connections shall be provided to meet the needs in any potential fire area. Hydrants that serve tank-farm areas shall preferably be of the four-headed pillar type with a riser of minimum diameter 100 mm.
Hydrant outlets and hose connections shall be so sited that they will be at least 15 m from potential fire areas, and shall be compatible with the requirements of the local authority.
The fire main shall be provided with isolating valves that are so spaced that no damage or repair to the pipe system (exclusive of arteries) will necessitate the shut-down of an artery or of a section of pipe of length exceeding 300 m in any area.
Fire hoses shall have fittings that are compatible with all the hydrant connections and shall be maintained for the worst-case fire scenario.
Normal finished foam is produced by introducing foam compound into water (usually at a rate of 3 % to 6 %) and then expanding the mixture with air for the type of low-expansion foam compound used. (The expansion factor is about 8 to 1.)
39
The foam may be applied by monitors that deliver it to the seat of the fire or, in the case of tanks, by dry risers or subsurface injection.
In the case of fixed-roof tanks, the application rate of the available mixure (solution) of foam compound and water for fire-fighting with low-expansion foam, can be calculated in litres per minute per square metre of total fire area. As a general rule, 6,5 L/min/m2 of fire area will result in the fire being extinguished (see NFPA 11).
Depending on the design of the tank, foam may be applied either by direct projection or by means of dry risers. In the case of floating-roof tanks, it is usual to design fire-fighting facilities that cater for rim-seal fires only.
This is most commonly done by applying low-expansion foam to the seal area. Vaporizing liquid systems are also used, especially in the case of crude-oil tanks. When foam is used, dry risers and foam dams shall be provided for.
An alternative method of applying foam is by injection via the base of a storage tank through product lines or special inlets (see NFPA 11). To avoid foam dilution, it is important to ensure that any injection point is above the water level of the tank bottom. Foams suitable and approved for base injection should be used.
Sufficient foam compound should be stocked to cater for the largest extinguishable fire in the greater of a fixed-roof tank and the largest possible spill area for 1 h, plus a complete reserve charge to cover the possibility of a second fire. Furthermore, it is recommended that some of the calculated requirements be held in terms of the mutual-aid arrangements between local authorities and industry.
Conveniently placed hand-held fire extinguishers or large mobile fire extinguishers, or a combination of these, shall be provided, which shall comply with SANS 10400 (see section TT 37).
The servicing of portable fire extinguishers shall comply with the requirements of SANS 1475-1.
For ready reference in an emergency, a layout plan of the site shall be displayed in an easily accessible location so that authorized persons can have easy access to it. The plan shall indicate the position and the nature of the contents of all product tanks, product pipe lines and valves, as well as the positions of water pipelines, hydrants, fire appliances, the fire control centre, emergency stop buttons, and access routes for fire-fighting equipment to reach all parts of the plant.
The plan shall also indicate the location of fire-fighting equipment and foam storage, including the quality and type of foam stored.
A notice on which the telephone numbers of the fire service and other emergency services are clearly recorded, shall be displayed near every telephone, at the control centre and at the gate of the site.
40
All tanks shall have their numbers painted on in two positions, one that is visible from the fire-service access route and the other opposite it, as follows:
All fire points (equipment and hydrant points) shall be clearly identified by the appropriate signs in accordance with SANS 1186-1 or an approved international standard. It is recommended that retro-reflective materials be used for this purpose. (See also 7.11.)
Portable and mobile fire-extinguishers shall comply with an approved standard (for example, SANS 1910).
Amdt 2
Dry-chemical powders shall be of a type that complies with SANS 1522 and is compatible with the intended application.
All fire-extinguishers shall be protected from the weather.
Fire-fighting hoses shall comply with an approved standard (for example, SANS 543).
Hoses shall be inspected at least once every calendar year by a designated person. Hoses found to be defective on inspection shall be replaced or repaired immediately.
NOTE A record should be kept that shows the date of each inspection and is signed by an appointed responsible person. (See also 7.16.4.)
Fire-fighting hoses shall be housed or stored in weatherproof containers when not in use.
Couplings for hoses, branch pipes, nozzles and connectors shall comply with SANS 1128-2.
All couplings shall be compatible with the local authority’s fire-fighting equipment.
All hydrants shall comply with SANS 1128-1 and shall be provided with rubber or plastic protective caps.
41
Fire alarms shall be of such volume and tone that they are clearly distinguishable from background noise and are audible, under prevailing wind conditions, anywhere along the perimeter of the site.
Where an alarm is electrically powered, an independent source of power shall also be available.
NOTE Hand-cranked or compressed gas units may also be used.
An approved means of direct emergency communication with local emergency services shall be available.
Foam compound shall comply with an approved standard. A knowledge of the compatibility of different foam compounds with one another and with dry chemicals, when used simultaneously in fire-fighting, is essential, since outside bodies, such as the local authority, might use different compounds. Regular quality tests shall be carried out in accordance with the manufacturer’s recommendations.
NOTE It is recommended that low expansion foam is used.
Foam compound types shall be suitable for the risk presented by the product on hand. All foam compound containers shall be clearly marked, appropriate to the type of compound. In this regard, expert advice shall be obtained from approved standards or from the manufacturer (or from both) (see SANS 1910 or NFPA 11).
Amdt 1; Amdt 2
Foam compound that is corrosive shall be stored in suitable containers.
All fire-fighting equipment shall be painted a distinctive red (A11 signal red or A14 poppy red, see SANS 1091). Notices shall be displayed in accordance with the requirements of SANS 1186-1 and the location of equipment that is not visible shall be clearly indicated. (See also 7.9.4.)
All selected key employees shall be trained and remain competent to deal with all possible emergencies and shall be conversant with the principles of fire-fighting and the operation of the fire-fighting equipment provided in their work environment.
An adequate number of employees shall be trained to stand in for absent trained key employees during periods of leave (including absences due to sickness) and on public holidays.
Records shall be kept of all training, as required by the OHS Act, 1993. (See also 7.16.4.)
After key personnel have been trained, fire drills shall be conducted regularly to maintain a competence level. Records shall be kept of all fire drills, as required by the OHS Act, 1993. (See also 7.12.)
42
It is essential to co-operate closely with the local fire authorities and to ensure that the fire brigade knows in advance the layout of the depot, what equipment and facilities are available, where they are located, and how they are used.
It is essential that an adequate joint plan of action in the event of a fire or other emergency be agreed upon in advance with the fire authority concerned, taking into account aspects such as the nature of the product stored and special risks (if any) that exist in the depot. (See also 7.16.3.)
Warning notices or symbolic safety signs (or both) shall be displayed at all entrances to hazardous areas, in accordance with the requirements of SANS 1186-1.
All portable and mobile fire-exinguishers shall be examined and tested periodically in accordance with SANS 1475-1 or the manufacturer’s instructions.
All fire-fighting equipment and systems shall be inspected once every calendar year by a competent person.
A fire practice shall be carried out once every calendar year, and shall include the local fire department’s personnel and appliances. (See also 7.14.)
Records of all inspections, tests and practices shall be kept by the designated person, and any shortcomings shall be rectified as soon as possible. These records shall be made available for inspection at any time during normal working hours. (See also 7.10.2.)
It is assumed that the layout of the depot, the type of plant and equipment installed, and the methods of operation are fully in accordance with the relevant recommendations given in this part of SANS 10089, and that familiarity and general compliance with ordinances, the applicable regulations framed under the OHS Act, 1993, and any other applicable regulations are ensured.
All accidents and dangerous occurrences shall be reported to the designated person or safety representative, who shall arrange for medical attention for the injured and for the elimination of unsafe conditions or unsafe actions, or both.
The following specific safety and protection measures shall be provided for in accordance with the OHS Act, 1993:
Contact with petroleum products and the associated dangers require that the following points be attended to:
Before any extensions can be made to an existing depot, a full risk analysis in terms of the legislation of the Major Hazard Installation Regulations (see the OHS Act, 1993) shall be made. Any maintenance of or extensions or repair work to a petroleum depot shall follow but not be limited to the following procedure:
44
The utmost vigilance is required to ensure that deviation from regulations is avoided, particularly when personnel are engaged in work in hazardous areas or when the staff of an outside contractor are employed.
During such operations, tanks and plants that have been used for a class II petroleum product shall be treated as if they had been used for a class I product.
Tanks and items of plant that have been used for a class III petroleum product present a reduced risk, and do not require the same precautions as in the case of a class I or a class II petroleum product. Nevertheless, care is still necessary, and in the case of repairs and maintenance proceed with caution, bearing the proximity of any class I or class II plant in mind.
When any hot work is to be carried out in a hazardous area that contains a petroleum product, a high degree of control and supervision shall be maintained. A permit that authorizes the work shall be issued in writing in accordance with 9.8. (See also annex C.)
NOTE All petroleum products become flammable when heated to their flash points.
Repairs or alterations shall not be permitted on any plant or equipment while such plant or equipment is in use (for example, when a tank or vessel is being loaded or unloaded). The local fire-fighting services shall be informed when water is not available or when any work is being carried out on major fire-fighting installations.
When repairs or alterations necessitate the dismantling of essential items of plant such as valves, pumps and pipelines, a specific notice shall be issued to all concerned. The work shall not be started until acknowledgement of the notification has been received.
No hot or other hazardous work shall be started inside a tank or vessel in which a class I, a class II, or a class III petroleum product has been stored until such time as the tank or vessel has been inspected, a gas-free certificate has been issued (see 9.8), all pipelines have been disconnected and all relevant authorities have been notified.
No person shall be allowed to enter a tank or vessel that has not been declared gas-free unless such person is equipped with suitable breathing apparatus. An observer shall be stationed at the manhole whenever work is to be done on such tank or vessel. Observers shall be instructed to watch the workers carefully and to take immediate action or summon assistance if any person(s) collapses(collapse) inside the tank or vessel.
Observers and other rescue personnel shall be equipped with the proper safety gear so that they themselves will not succumb during rescue operations. Special attention shall be given to the manholes, scaffolding (see SANS 10085-1) and rigging, to ensure safe entry and exit. When tank cleaning, repairs or alterations are involved, the special instructions applicable to this type of work shall be rigorously observed. (See also 9.9 and annex C.)
Amdt 2
In the event of a broken connection, no reliance shall be placed on closed valves. Complete drainage shall be effected and openings shall be closed properly by means of blank flanges or line
45
blinds. Any spillage of product shall be collected and disposed of in an acceptable way. When continuity in a pipeline is broken, the work area shall be bridged with a heavy electrical jumper cable to reduce the risk of sparks from stray or induced currents.
An accredited person shall certify that the electrical equipment has been isolated and locked out safely before any repair, adjustment or test is commenced. Warning notices (symbolic signs) shall be hung onto or affixed to main switches or circuit-breakers, to prevent accidental switching-on while repairs are in progress. After repairs have been completed, an accredited person shall certify that the apparatus is in order, both mechanically and electrically, before it is brought back into use. (See SANS 10089-2.)
Only authorized personnel shall be able to lock out equipment. All lock-out systems shall comply with the requirements of the OHS Act, 1993.
For certain types of plant and equipment such as pressure vessels, cranes, and electrical apparatus, an adequate system of keeping permanent records shall be maintained for all repairs, inspections and tests, in compliance with the OHS Act, 1993.
All staff engaged in operational maintenance duties shall be fully acquainted with the requirements of the safety regulations in terms of the OHS Act, 1993.
Maintenance and inspection work shall be planned and supervised by responsible members of staff, who shall ensure that all relevant precautions are observed.
When casual and contractors’ labourers are employed, they shall be familiarized with all the relevant precautions adopted by the depot. The necessary precautions to be taken shall have been thoroughly explained to them before any work is commenced. (See section 13 (Duty to inform) of the OHS Act, 1993.)
When such labourers are employed in or adjacent to a hazardous area, strict supervision shall be arranged to ensure that all relevant precautions are observed.
When mobile plant is temporarily stationed in a hazardous area for maintenance, repair or other purposes, care shall be taken to ensure that the plant is of such construction that it is not likely to cause a fire by the emission of sparks or flames, or by any other source of ignition.
No plant belonging to a contractor shall be used on the premises without the written permission of the depot manager or his authorized representative.
46
The use of vehicles and plant on the site, particularly in hazardous areas, shall be defined and controlled and the routes to and from such areas shall be clearly indicated.
Personnel or contractors shall be prevented from gaining unauthorized access to a hazardous area and, when necessary, temporary fencing, portable barriers or screens shall be provided.
Warning notices shall be prominently displayed where necessary (see also 7.15 and 9.2.5).
To ensure safety, construction and repair work shall only be performed in a depot if written permission has been granted by the manager or his authorized representative. All permits issued shall be specific with regard to their purpose. A permit can be cancelled at any time if conditions are considered to have become unsafe. (See examples in annex C.)
General or cold-work permits shall be issued by the designated person to allow any work within the depot that does not involve hot work (which could cause ignition) or entry into confined spaces. (See examples in annex C.)
Gas-free certificates shall be issued by a person who has received formal training in the properties of flammable liquids and in the operation, calibration, maintenance and use of the type and model of gas testing device employed to determine the presence of hazardous vapours in the workplace, and who has been vested (in writing, by the employer) with authority to issue gas-free certificates (see 9.10.2). (See examples in annex C.)
Hot-work permits shall be required wherever hot work is to be done in an area in which flammable vapours might exist. A hot-work permit is issued on the condition that a normally safe area remains safe for the duration of the work, or that an area which is normally hazardous be converted into a temporary safe area for the duration of the work. Hot-work permits shall be issued by a person who has been vested (in writing, by the employer) with authority to issue hot-work permits. (See examples in annex C.)
Confined-space entry permits shall be required whenever it is necessary to enter a confined space that contains, or has contained, a flammable or toxic atmosphere and from which easy and ready escape is hampered. A gas-free certificate shall also be required. Confined-space entry permits shall be issued by a person who has been vested (in writing, by the employer) with authority to issue confined-space entry permits. (See examples in annex C.)
The designated person may subdelegate the extension of the period of validity of permits that he has issued to a responsible person, provided that conditions do not change in a way that would constitute an increased hazard.
47
It is difficult to recommend hard and fast safety rules that should be observed during maintenance work in operating plants, and the recommendations given in this part of SANS 10089 might have to be modified or adapted. Pay due regard to the petroleum operations being carried out at the time, and to the weather, humidity, wind direction, topographical features of the site, and the availability of assistance from outside should emergencies arise during the work.
Unless it is unavoidable, no hot work, rivetting or welding shall be permitted within 15 m of a tank or vessel that contains class I or class II petroleum products, or within 6 m of one that contains class III petroleum products.
These distances are minimum distances that might have to be increased because of local conditions or specific circumstances. Bear in mind also that an area that has been classed as safe could become hazardous owing to a change in wind direction. In addition to professional judgement, use a gas detector to assess the conditions in each situation.
Ensure that any working tank of which any part is within these distances, is emptied, and that a gas-free certificate is issued by a qualified person. Where these distances cannot be adhered to, a qualified person shall supervise the work (throughout its duration) and such person shall strictly enforce the necessary precautions.
In hazardous areas, special precautions shall be taken, such as the temporary resiting or supplementing of fire equipment to cover an emergency or, when it is deemed expedient, the provision of fire-watchers to detect incipient fire and to bring first-aid and fire-fighting equipment into immediate use. Brief but explicit instructions shall be given to any contractor regarding the action to be taken in the event of a fire. (See also clause 6.)
NOTE If a plant falls (because of its power rating or for any other reason) under the jurisdiction of the Chief Inspector appointed in terms of the OHS Act, 1993, the Chief Inspector is the overriding authority, and recommendations given in this clause are additional to and subject to compliance with the requirements issued by the Chief Inspector.
A tank that has contained a volatile hydrocarbon might have to be gas-freed before the tank can be cleaned or repaired. (This is done to protect persons from the toxic and asphyxial effects of the hydrocarbon, and to make the repair operation safe from the hazard of fire.)
When a combustible-gas indicator (gas detector) has been used to confirm freedom from flammable vapours, the atmosphere within the tank could still be deficient in oxygen or could contain toxic components. In all cases of doubt, appropriate chemical tests shall be carried out. (For more detailed information regarding the cleaning of leaded gasoline tanks and the disposal of sludge, refer to OCTEL directive Lead alkyl antiknock compounds (see 2.2).)
A gas-free certificate is required when:
In the latter case, special attention shall be given to the oxygen content, as required by the OHS Act, 1993.
Hydrocarbon vapours are denser than air and, although they can be dispersed easily and safely by a light breeze, a dangerous concentration can travel a considerable distance in a still atmosphere. The large volume of an air-and-hydrocarbon-vapour mixture that could be released during a gas-freeing operation can travel beyond the limits of the usual safety distances, and it is therefore recommended that all possible sources of ignition in the entire area be eliminated at all times during gas-freeing. Persons shall be kept clear of the bunded area and the down-wind area as far as possible, especially where gas and air from the tank cannot be discharged at a high level.
Mixtures that contain about 1 % to 10 % (by volume) of petroleum vapours in air are flammable. If there is less than 1 % or more than 10 % of vapour, the mixture will be too lean or too rich to burn. The limiting values of 1 % and 10 % are known as the lower explosive limit (LEL), and the upper explosive limit (UEL) respectively.
NOTE The approximate relationship between temperature, Reid vapour pressure, and explosive limits of petroleum products is given in figure 2.
The quantity of vapour in an air-and-vapour mixture can be measured by means of a gas detector.
NOTE Gas detector scales are graduated from 0 to 100, their graduation being based on the lower limit of flammability of 1 %. A reading of 50 indicates 50 % of the lower limit of flammability (i.e. the mixture contains 0,5 % of vapour), and a reading of 20 on that scale indicates 0,2 % of vapour.
The instrument used for recording the concentration of this vapour shall be of approved design and shall be regularly calibrated and tested for accuracy.
Vapour concentrations and the corresponding safeness of working conditions are given in table 6.
1 | 2 | 3 |
---|---|---|
Gas detector scale reading, R | Actual percentage of petroleum vapour (where lower limit is 1 %) | Working conditions |
0 ≤ R ≤ 1 | 0 to 0,01 | Safe to work in lead-free atmospheres without breathing apparatus and to use naked lights and spark-producing or flame-producing equipment |
1 < R < 4 | Exceeding 0,01 but less than 0,04 | Safe to work in lead-free atmospheres without breathing apparatus but unsafe to use naked lights or spark-producing or flame-producing equipment |
4 ≤ R ≤ 10 | 0,04 to 0,1 | Safe to work in lead-free atmospheres without breathing apparatus for short periods. Unsafe to use naked lights or spark-producing or flame-producing equipment |
R > 10 | Exceeding 0,1 | Unsafe without breathing apparatus. Unsafe to use any tool or equipment |
49
Figure 2 — Approximate relationship between temperature, Reid vapour pressure and explosive limits of petroleum products
50
The methods of gas-freeing in 9.10.7.1 to 9.10.7.4 can be used, either singly or in combination.
This method is recommended in the case of storage tanks where the use of steam or water is impracticable or undesirable.
Gas-freeing by flooding with water has the disadvantage that it cannot be relied on to remove all petroleum vapour, liquid, and solid residues. Furthermore, before the method is adopted, the tank and its foundations have to be verified as being capable of sustaining the mass of the vessel filled with water. To avoid the build-up of a static charge when this method is used, the flooding water shall be introduced at the base of a tank and, if a hose pipe is used, the flow rate shall be kept low and the nozzle shall be electrically earthed.
This method can be used in the case of small storage tanks and medium-sized insulated tanks. In the case of certain products, complete removal by steam is not always possible, and a residue might remain that could be ignited during welding. Only low-pressure steam shall be used, and steam hoses shall be electrically bonded to the tank shell.
NOTE Steam degassing can present the danger of tank implosion should rapid steam condensation occur.
This method can be used where it is impossible to displace flammable gases or liquids with steam, water or air because of their effect on the contents of the tank. This method involves a danger that, when air later displaces the inert gas, any pyrophoric deposits that are present could burst into flame. In addition, the tank atmosphere will not be fit to breathe after purging and the inert gas will have to be swept out with air and a test for sufficiency of oxygen will have to be carried out before anyone can enter without breathing apparatus.
The procedure for the gas-freeing of tanks varies according to the type of tank.
Gas-freeing does not ensure the safety of persons who enter tanks that have contained leaded petrol unless appropriate protective clothing is worn.
Conduct gas-freeing operations only under the direct supervision of a designated person, and use the appropriate procedure described in 9.10.8.1 to 9.10.8.4.
Carry out the following procedure:
As petroleum vapours are denser than air, it is preferable that fresh air be drawn into the tank at a high level and that the effluent vapour be extracted, via flexible trunking from a top manhole, at a low level (about 2 m above the tank floor).
If possible, do not expel air from a low level (for example from a manhole at the bottom or side), since vapour will concentrate in the bund area and create a hazard.
Continue ventilation until gas detector tests show either a safe concentration of, or freedom from petroleum vapour. A tank can be considered free from gas when a series of gas detector tests are carried out at 5 min intervals over a 30 min period at several places in the tank and all gas detector readings are below 4. Before anyone starts working in the tank, provide maximum dilution of the atmosphere in the working area by moving the air inlet to a low level. To prevent any build-up of flammable vapour when sludge is disturbed, continuous ventilation is necessary throughout a tank-cleaning operation. Discontinue forced ventilation and tank-cleaning during an electrical storm.
Use a gas detector, as and when required, to check that tanks that have been freed from gas remain gas free throughout the period during which maintenance work is being carried out.
Follow the same general procedure as detailed in 9.10.8.1. Facilitate entry by supporting the floating roof by its extended vertical columns (or other means), and open roof fittings, manhole covers, and dip hatches to facilitate ventilation. The use of wind-sails on this type of tank is often not practicable, but ventilation can be accelerated mechanically by the use of wind-scoops made of suitable material and located in the side manholes, or by the use of fans or eductors. When testing for vapour concentration, include the space in the tank that is above the roof and inside the pontoons. Open and ventilate pontoons and double decks, and use a gas detector to check each such space individually.
Ensure that water-drainage systems are clear of product, by opening and flushing them.
After draining the horizontal tank as completely as possible of its contents, remove the manhole covers and use water as a flushing medium. Before flushing the tank, ensure that all pipelines are disconnected and blanked off and all apertures fully opened. Ventilation can be accelerated by means of a wind-sail or by mechanical means.
Follow the same general procedure as in the case of fixed-roof tanks (see 9.10.8.1), but remember that it is essential to ventilate access chambers, valve chambers, and tunnels ancillary to the tank as well, and to include these places in the testing procedure.
The cleaning of these tanks is a hazardous operation owing to the presence of toxic organic lead derivatives in the atmosphere and in the sludge and scale from the inside walls and roofs of the
52
tanks. The tanks therefore require special treatment in the cleaning process, and the instructions issued by the manufacturer of the lead compound regarding the procedure and the safety measures to be adopted have to be observed rigidly. Tanks that have, at any time, contained a leaded product shall carry, near each manhole, a permanent warning notice to this effect.
When the cleaning of a tank involves the entry of persons and the tank cannot be completely gas-freed and maintained in that condition throughout the entire operation, the following precautions shall be observed:
53
In the case of a tank that is free from gas and can be maintained in that condition throughout the entire operation, only the precautions given in 9.11.2.1(a), 9.11.2.1(f), and 9.11.2.1(j) have to be observed, while the workers should still be provided with suitable clothing (see the OHS Act, 1993).
Tanks that are being cleaned under gas-free conditions may be illuminated as in 9.11.2.1 (i), or by low-voltage a.c. (below 50 V) portable lighting equipment. The supply cable to the flameproof transformers for low-voltage lighting equipment shall always be so supported that the cable is held clear of the ground, and a transformer shall never be taken inside a tank.
Rail tank vehicles, road tank vehicles and storage tanks of limited size can be conveniently cleaned by equipment operated from outside the tank and in these cases only the precautions given in 9.11.2.1(a) and 9.11.2.1(j) have to be observed.
All effluent and excess water shall be treated before it is passed into the drainage systems. (See also 4.9.5.)
Provided that tanks that previously contained a class III product are ventilated adequately during cleaning operations and that persons working in them wear suitable protective clothing, no special precautions are necessary.
NOTE Rail transportation falls within the jurisdiction of Spoornet. In the case of road transportation, compliance with the relevant provisions of the Road Traffic Act and with the requirements of the local licence authority is necessary.
All bulk road and rail vehicles for petroleum products shall be constructed in compliance with an approved standard and shall conform to sound engineering design. (See also SANS 1518, SANS 10228, SANS 10229-1, SANS 10231, SANS 10232-1, SANS 10233 and SANS 10263) The regulations for the transportation of hazardous goods and the local by-laws shall be adhered to.
Amdt 1; amdt 2
The design and operation of the installation shall be such that the storage and handling facilities will not cause contravention of the National Water Act, 1998. In particular, all reasonable steps shall be taken to prevent pollution of both underground water and surface water.
All waste shall be disposed of in an approved manner. (See also 4.9.)
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(informative)
Water requirements for fire-fighting purposes should be determined for the highest fire risk with the largest fire surface area in a depot.
The fire risks in a depot should be determined by means of a risk assessment.
The definitions in A.3 and research for this annex have been collected from the various publications as listed below:
AIChE (CCPS), Guidelines for chemical process quantitive risk analysis.
Amdt 2
AIChE (CCPS), Guidelines for hazard evaluation procedures.
Amdt 2
API RP 2030, Application of fixed water spray systems for fire protection in the petroleum and petrochemical industries.
Amdt 2
NFPA 11, Low-, medium-, and high-expansion foam systems.
NFPA 15, Water spray fixed systems for fire protection.
UNEP IE/PAC Technical Report No. 12, Hazard identification and evaluation in a local community.
For the purpose of this annex, the following definitions apply.
an unplanned event or sequence of events that results in undesirable consequences. An incident with specific safety consequences or impacts
an event that has a degree of probability (likelihood) of occurring, or for which reasonably practical mitigating actions can be taken by the owner of the depot to minimize the consequences (or both)
the direct, undesirable result of an accident, usually involving a fire, an explosion, or the release of toxic material. Consequences may be expressed as either quantitative or qualitative estimates of the effects of an accident in terms of factors such as health impact, economic loss, and environmental damage
NOTE Severity is very often used as a synonym or to express the degree of consequence.
55
an occurrence related to equipment performance or human action exernal to the system that causes a system upset. An event is either the cause of or a contributor to an incident or accident, or is a response to the event that initiated an accident. Fire, explosion, and toxic release are typical events
any event that occurs external to the system considered
NOTE Examples are: lightning, extremely unusual weather conditions, earthquake, landslide, flooding, actions of third parties or failure of their equipment outside of the property of the depot but impacting on the depot.
a chemical or physical condition that has the potential to cause damage to people, property, or the environment
NOTE A common synonym is “risk source”.
the analysis of the significance of hazardous situations, or other processes or activity. It uses qualitative techniques to pinpoint weaknesses in the design and operation of facilities that could lead to accidents
the pinpointing of material, system, process, and plant characteristics that can produce undesirable consequences through the occurrence of an accident
the loss of hazardous material from containment or the release of hazardous forms of energy (for example, in a “near miss")
an event that is extremely improbable (with, for example, a likelihood of less than 1 in 1 000), or for which “reasonably practical” measures to minimize the consequences are beyond the capabilities of the owner of the depot, or both
a measure of the probability or expected frequency of an event’s occurrence
an expected chance for certain events to happen within a certain period of time
the combination of the expected probability of an event and the consequence of that event. It is a measure of economic loss or human injury in terms of both incident likelihood and the magnitude of loss or injury. (Risk = Severity × Probability.)
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the development of a quantitative estimate of risk based on engineering evaluation and mathematical techniques for combining estimates of incident consequences and frequencies. It is the systematic identification and evaluation of risk objects and hazards
the process by which the results of a risk analysis (i.e. risk estimates) are used to make decisions, either through relative ranking of risk reduction strategies or through comparison with risk targets
the process of combining the estimated consequences and likelihood of all incident outcomes from all selected incidents to provide a measure of risk
any object that could institute a risk within the perimeter of a bulk storage depot (for example, tanks, tank bund, loading racks, rail sidings, warehouses, workshops, etc.)
objective-based risk criteria established as goals or guidelines for performance
the possible event with the worst consequences. There are three types of “worst case":
(See also UNEP IE/PAC Technical Report No. 12.)
There are numerous hazard evaluation techniques. Each technique has a specific purpose, benefits, costs and limitations. Some are qualitative techniques whilst others are quantitative methods, and a few are a combination of qualitative and quantitative methods.
The most common hazard evaluation techniques are:
The most suitable and practicable techniques for a petroleum bulk depot are any of the following:
The technique(s) used for the hazard evaluation shall be at the discretion of the responsible engineer.
NOTE It has been found that the application of simple qualitative assessment techniques for depot assessments give results that are very similar to those of the more complicated in-depth techniques.
In addition to the hazard evaluation listed in A.4, there is another method, called quantitive consequence analysis (QCA). In most cases it is sufficient to estimate the order of magnitude of the consequences. It is not always necessary to estimate in great detail. In a few cases it may be necessary to conduct QCA for a depot, for example when modelling the spread of gases (toxic or LPG) and their effects.
NOTE This example only gives the key features of a full analysis.
The following details deal with PHA, one of the techniques listed in A.4, to serve as a typical illustration of a major risk analysis approach. The primary components of a PHA are:
In A.6.1, the specific example of a PHA for a fuel depot is outlined. 58
List the various hazardous events.
Follow each event through to its conclusion (without any controls applied) and record the consequences.
Identify and record existing active and passive controls which would limit the probability of the event or the severity of the consequences.
NOTE
Review the critical factors such as operating procedures, training, fire protection systems and emergency shutdown devices which could influence the likelihood of an event occurring, or the severity of the incident. The information obtained from such a review is then considered when determining a risk index value for the event.
Once the definition and ranking of likelihood and consequence are determined and tabulated, a corresponding 5 × 5 matrix can be constructed (see the example in figure A.1).
The risk index (RI) for any event is calculated as the product of its likelihood and its consequence value in the risk matrix.
The first steps in drawing up a risk matrix are to define the ranking of likelihood and the ranking of consequence (or severity) of events.
Both the likelihood and consequence (or severity) of various events are given a ranking value on a subjective scale, as in the example of a five-point ranking given in table A.1.
The standard definitions of likelihood and severity may be modified to accommodate local factors relevant to the installation being evaluated and 3 × 3 or 4 × 4 risk matrices may be used. Examples that illustrate the use of likelihood and consequence definitions and ranking for a particular case study are given in tables A.2 and A.3.
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Figure A.1 — Typical (5 × 5) risk matrix
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1 | 2 | 3 |
---|---|---|
Ranking | Consequence or severity | Likelihood |
1 | Unimportant/Negligible:
|
Highly improbable < once per 1 000 years |
2 | Limited/Minor:
|
Improbable Once per 100 – 1 000 years |
3 | Serious / Marginal:
|
Infrequent Once per 10 – 100 years |
4 | Very serious/Significant:
|
Frequent Once per 1 – 10 years |
5 | Catastrophic:
|
Very probable More than once per year |
1 | 2 | 3 |
---|---|---|
Likelihood designation | Likelihood ranking | Description/Definition |
Frequently | 5 | This type of event has occurred at this facility one or more times during the life of this type of process OR piece of equipment. |
Probable | 4 | It is expected that this event will occur at this facility at least once during the life of this type of process or piece of equipment. |
Possible | 3 | This event may occur at this facility at least once during the life of this type of process or piece of equipment. |
Seldom | 2 | This event is unlikely to occur at this facility, but it has occurred at least once somewhere else for this type of process or piece of equipment. |
Unlikely | 1 | This event will not occur at any of the company’s depots, and the company is unaware of any other facility where it has occurred under similar circumstances. |
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1 | 2 | 3 |
---|---|---|
Severity designation | Severity ranking | Characteristics of the event |
Catastrophic | 5 |
|
Significant | 4 |
|
Marginal | 3 |
|
Minor | 2 |
|
Negligible | 1 | No loss of production, no injuries, or minor equipment loss. |
The severity values used for a risk assessment study should be based on factors that are mutually agreed upon with the respective company management before use. Some critical aspects in the above example are:
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Risk mitigation involves the implementation of measures that reduce the risk index (RI) to an acceptable value. Such measures could be either passive or active controls (see A.6.1.4) or both. If the RI for an event can be reduced to an acceptable level by passive control alone, and it is cost effective, then there is obviously no justification for additional fire protection systems.
The example in A.6.1 and A.6.2 is only one typical example of one of the risk assessment techniques.
NOTE Generally, the oil industry worldwide tends to consider only those recommendations that would be necessary to reduce the risk index for an event to below 9. Additional mitigation measures could be taken to reduce the RI further, but might not be cost-justified. RIs of 8 and below are considered acceptable risks which the oil industry is prepared to take.
Water requirements in the management of fire effects (see note) are expressed as total flow in litres per minute and calculated pressure.
NOTE The management of fire effects is the fire-fighting strategy which involves any one or a combination of the following, often in the priority order given:
The water is applied together with foaming agents for extinguishing and, if required, for control of a petroleum fire. (Foaming agents are not necessarily required for safeguarding exposures and for control or isolation purposes.) Some typical events which are generally included in risk assessments are given in A.7.1 to A.7.4. The results of a risk assessment for a depot will identify the highest risk with fire area that has the largest horizontal surface area.
The determination of water requirements is dealt with in the latest edition of NFPA 11 or in the information service of the supplier of foam and equipment. The following shall be taken into account when determining water requirements:
NOTE For the calculation of the minimum pressure see 7.8.8.
The determination of cooling water requirements (as in (a) to (c)) is dealt with in the latest editions of NFPA 15 and oil industry specific API Publication 2030.
This amounts to 15,1 to 30,3 litres/min/linear metre circumference of the tank for a fixed cooling system; or 30,3 to 62 litres/min/linear metre for portable equipment.
Since the exact location of the exposing fire or the amount of liquid in the exposed tank may not be known before the fire occurs, total protection would require that the entire tank be sprayed. However, water sprayed on surfaces that are not exposed to fire is wasted and takes resources from other fire suppression efforts. Application of cooling water by hose streams and monitors is generally a more efficient use of available water.
Take into account any water required for the protection of fire-fighters and to be used for isolation of adjacent tanks if deemed necessary, and determined by the number of hose streams required at 250 to 450 litres per minute per hose.
The largest tank is assumed to be full when it ruptures, spilling its contents into the bund. Refer to the latest edition of NFPA 11 and to the supplier(s) of foam and equipment for foam, equipment and water requirements. The following have to be taken into consideration:
An allowance should be made for the application of foam into the failed tank if it has not totally collapsed. Calculate the water flow for foam application as in A.7.1.1.
If remote bunding was provided as additional containment for the spill, then follow the same calculation as in A.7.2.1. Generally, the principle of remote bunding is to contain a spill in a safe location where there is no threat to adjacent facilities. If so, foam application need only commence in the remote bund once the fire in the main bund has been extinguished.
The required total water flow is equal to the requirement as determined in A7.2.1 or A.7.2.3, whichever is the greater, based on the principle of fighting one bund fire at a time.
The total water flow shall be available from the fire main for at least 1 h. The total flow as given in A.7.2.4 should be guaranteed for the minimum application time for the type of application and for the type of product as defined in A.7.2, based on the principle of fighting the ground and bund fire first before fighting the tank fire.
The considerations in A.7.3.1 to A.7.3.5 are applicable to both bulk truck loading racks and rail sidings.
Distinguish clearly between the various types of event.
One event is the release of the total contents of a truck or tank car into the containment area and oil/water separator(s) or remote impounding area if provided, or both.
Another event could be the release of only a quantity of product which depends on the effectiveness of the emergency shut-off response.
NOTE The maximum allowable emergency shut-off response time should not be more than 2 minutes. The maximum anticipated spill in litres is then equal to the product of this response time (in minutes) and the spill release rate (in litres per minute).
Yet another event could be an explosion due to switch loading and the release of the contents of the tanker.
NOTE A bulk truck has a far greater likelihood of releasing the contents of at least one compartment (or more) than a tank car, because a bulk truck is constructed of aluminium and is loaded with closed domes for
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bottom loading, and emergency venting is generally not provided for. Tank cars are constructed of steel and loaded with open domes, thus providing adequate emergency venting. All of this should be considered in the risk assessment.
Yet another event is the derailment of a tank car which could result in the total contents of the tank car being released as in A.7.3.1.1, or a portion of the tank car contents being released.
Design for the highest risk, as determined by a risk assessment of the various events.
Determine the spill fire area for the highest risk.
Refer to the latest edition of NFPA 11 and to suppliers of the foam and equipment to determine foam water requirements.
Calculate the foam water flow required in litres per minute.
The calculation of the water requirement should take into account the following:
Calculate the foam water required in litres per minute.
Ensure that cooling water for pressure fires (minimum 2 hoses, streams of 125 to 250 litres per minute) is provided if no fixed foam/water sprinklers or fixed monitors exist or only portable foam equipment is provided. Generally, pressure fires in depots would be extinguished by closing remote valves and switching off pumps, and a pressure fire on a tanker could be extinguished by dry chemical powder extinguisher. Additional water requirements for fire-fighters might be required for isolation if remote isolation is not provided (determine the number of hose, streams of 250 to 450 litres per minute). Hence calculate the total water flow requirements.
The total water flow requirements should be available for at least 1 h.
Refer to NFPA 11 and the suppliers of foam and equipment to determine the total water flow requirements. The calculation of the water requirement should take into account the following:
Calculate the total water flow requirements.
The total water flow requirements should be available for at least 1 h.
NOTE In the case of other operational spill fire events such as at pump manifolds etc., the determination of water requirements would be similar to the event given in A.7.4. Allowance could be made for cooling hose streams/reels and water for isolation, if required.
If stone ballast for the containment of operational spills is provided such that the volume of any anticipated spill can be completely contained within the voids, then the spill open surface area may be considered as (open) void area at the stone ballast surface, provided that the maintenance of these conditions are guaranteed.
The fire surface area may be considered as the (open) void area at the stone ballast surface and foam water requirements calculated as in A.7.4.1 and A.7.4.2.
NOTE It is important that allowance is made in the expanded foam application technique, since expanded foam is designed to float and flow over the surface of the flammable liquid and will not readily flow over the stone ballast. This can be accomplished by use of, for example, hand-held foam nozzles and oscillating foam monitors. If fixed foam pourers are used it may be necessary to increase the application rate of foam/water solution or the number of foam pourers, or both, to ensure adequate coverage of the stone ballast surface area.
Adequate underground drainage should be provided to rapidly clear the voids from any previous spills and water to maintain the operational spill capacity of the stone ballast voids. The capacity of the stone ballast voids should be designed to handle the anticipated operational spill during worst case conditions, namely during the design storm (generally the 2 year storm is assumed). (As this poses significant practical problems, it is not considered a viable option by the majority of oil industry members.)
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(informative)
From the results of experiments and from plant operating data, it has been determined that the design of waste water separators should be based on the rate of rise of oil globules that have an average diameter of 150 urn. This globule size, although somewhat arbitrary, has been adopted for design purposes because satisfactory oil removals are achieved when a particle of 150 urn diameter is used as a basis for design or investigation.
The vertical rate of rise, Vt, of an oil droplet in water is given by the formula
Vt = 1,962 × 10–9 × Δσ × D2/η
Amdt 1; amdt 3
where
Vt is the vertical rate of rise, in metres per hour;
Δσ is the difference in densities between water and oil, in kilograms per cubic metre;
D is the diameter of the oil droplet, in micrometres; and
η is the dynamic viscosity of water, in pascal-seconds.
The interceptor should be so designed for a given water flow rate q that there is sufficient time for the oil globules to rise all the way from the bottom of the interceptor to the under-surface.
The design of the retention system around the spill origin and outlets should be able to cope even with the worst rainfall conditions and should therefore take into account the maximum rain intensity (this figure can be obtained from the Mean Annual Precipitation (MPA) map of the RSA), viz, 40 mm/h for both coastal and inland zones. Assuming that the rain water runs off as fast as it is deposited, the maximum runoff becomes
q = C.I.A/60000
where
q is the runoff flow capacity, in cubic metres per minute;
C is the runoff coefficient (e.g. 0,9 for concrete);
l the rain intensity, in millimetres per hour; and
A is the catchment area, in square metres.
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The horizontal velocity, Vh, is given by
Vh = q / Ac
where
Vh is the horizontal velocity, in metres per minute;
q is the runoff flow capacity, in cubic metres per minute; and
Ac is the cross-sectional area of the separator, in square metres.
An acceptable maximum horizontal velocity Vh, for the flow through an interceptor would be less than 0,91 m/min (3 ft/min or 55 m/h), or 15 Vt, whichever is the smaller.
The length of the separator, L, in metres, is given by
L = F (Vh/Vt) × d
where
F is a design factor (dimensionless); and
d is the depth of the separator, in metres.
The design factor F is the product of the short-circuiting factor, Fsc, which can be taken as 1,2, and the turbulence factor, F t, which is a function of the ratio of Vh to Vt:
F = Fsc × Ft
The American Petroleum Institute gives the following recommended values of turbulence factors:
Vh/Vt | Turbulence factor, Ft |
---|---|
20 | 145 |
15 | 137 |
10 | 127 |
6 | 114 |
3 | 107 |
Amdt 1
Furthermore, a separator should be designed within the following limits:
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A separator is to be designed to cater for runoff from a concrete area 50 m × 45 m = 2 250 m2, assuming a maximum rain intensity of 40 mm/h. The design temperature is 10 °C, and waste water through the separator contains diesel with a density of 860 kg/m3 at 10 °C.
q | = | C.I.A./ 60000 | |
= | 0,9 × 40 × 250/60 000 | ||
= | 1,35 m3/min | ||
Vt | = | 1,962 × 10-9 × Δσ × D2/η | Amdt 3 |
= | 1,962 × 10-9 × (997-860) × 1502/1,348 × 10-3 | ||
= | 4,487 m/h | ||
= | 0,0748 m/min | ||
Vh | = | 15 Vt | |
= | 1,122 m/min |
which is greater than 0,91 m/min, therefore use Vh = 0,91 m/min as a maximum.
To avoid excessively long separators, Vh should, in practice, be kept to a minimum. This can be done by increasing (within reason) the cross-sectional area of the separator.
Therefore assume | d | = | 1,3 m |
From | d | = | 0,5 × w |
W | = | 2,6 m | |
Then | Ac | = | d.W |
= | 1,3 × 2,6 | ||
= | 3,38 m2 | ||
and | Vh | = | q / Ac |
= | 1,35/3,38 | ||
= | 0,4 m/min | ||
Hence | Vh/ Vt | = | 0,4/0,0748 |
= | 5,34 |
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By interpolation between the listed turbulence factors,
Ft | = | 1,125 | |
So that | F | = | Fsc × Ft |
= | 1,2 × 1,125 | ||
= | 1,35 | ||
This gives | L | = | F (Vh/ Vt) × d |
= | 1,35 × 5,34 × 1,3 | ||
= | 9,37 m |
Therefore, the final dimensions of the separator would be:
length | = | 9,4 m; |
width | = | 2,6 m; and |
depth | = | 1,3 m. |
71
(informative)
72
73
74
75
76
77
78
As it is possible that work of an electrical nature in a most hazardous area will be carried out by technicians other than registered electricians (i.e. meter technicians, computer technicians, electronic technicians, etc.) electrical permits shall comply with the following requirements:
NOTE An illegible signature is not acceptable. The person concerned shall sign where necessary, and shall also print his name in block letters. |
79
(informative)
Safety distances for LPG facilities
LPG tank installation
For the recommended installation and safety distances of LPG tanks, refer to SANS 10087-1 and SANS 10087-3.
Figure D.1 — Recommended safety distances for LPG facilities
80
(informative)
NOTE Legislative bodies who wish to incorporate this part of the code of practice into any law in terms of Section 29 of the Standards Act, 1993, are requested to note that compliance with the international or foreign standards or publications listed here may not be enforceable under the incorporating law.
API RP 2030, Application of fixed water spray systems for fire protection in the petroleum and petrochemical industries.
Amdt 1; amdt 2
API RP 520-2, Sizing, selection and installation of pressure-relieving devices in refineries – Part 2: Installation.
Amdt 1
API Std 2510, Design and construction of LPG installations.
CKS 532, Fire extinguishing agent: aqueous-film-forming-foam concentrate.
NFPA 15, Standard for water spray fixed systems for fire protection.
Amdt 1
NFPA 22, Water tanks for private fire protection.
NFPA 30, Flammable and combustible liquids code.
NFPA 58, Storage and handling of liquefied petroleum gas code.
NFPA 69, Standard on explosion prevention systems.
Amdt 1
PD 5500, Specification for unfired fusion welded pressure vessels.
SANS 460, Plain-ended solid drawn copper tubes for potable water.
SANS 668 (SABS 668), The production of men’s Derby style protective boots and shoes (Goodyear welted, with stitched or stuck-on outer soles).
Amdt 3
SANS 669 (SABS 669), The production of men’s protective shoes (Goodyear welted, with stitched or stuck on outer soles).
Amdt 3
SANS 741, Industrial boots (including safety boots) with direct-vulcanized soles and heels.
SANS 809, Industrial body belts.
SANS 1151, Portable rechargeable fire extinguishers – Halogenated hydrocarbon type extinguishers.
SANS 1535, Glass-reinforced polyester-coated steel tanks for the underground storage of hydrocarbons and oxygenated solvents and intended for burial horizontally.
SANS 1774, Liquefied petroleum gases.
SANS 10019 (SABS 019), Transportable metal containers for compressed gas – Basic design, manufacture, use and maintenance.
81
SANS 10087-1, The handling, storage, distribution and maintenance of liquefied petroleum gas in domestic, commercial, and industrial installations – Part 1: Liquefied petroleum gas installations involving gas storage containers of individual water capacity not exceeding 500 L and a combined water capacity not exceeding 3 000 L per installation.
SANS 10087-3, The handling, storage, distribution and maintenance of liquefied petroleum gas in domestic, commercial, and industrial installations – Part 3: Liquefied petroleum gas installations involving storage vessels of individual water capacity exceeding 500 L.
SANS 10087-4 (SABS 087-4), The handling, storage, distribution and maintenance of liquefied petroleum gas in domestic, commercial and industrial installations – Part 4: Transportation of liquefied petroleum gas in bulk by road.
SANS 10089-3 (SABS 089-3), The petroleum industry – Part 3: The installation of underground storage tanks, pumps/dispensers and pipework at service stations and consumer installations.
SANS 10090, Community protection against fire.
SANS 10105-1, The use and control of fire-fighting equipment – Part 1: Portable and wheeled (mobile) fire extinguishers.
SANS 10105-2, The use and control of fire-fighting equipment – Part 2: Fire hose reels, hydrants and booster connections.
SANS 10119 (SABS 0119), Reduction of explosion hazards presented by electrical equipment – Segregation, ventilation and pressurization.
SANS 10131, Above-ground storage tanks for petroleum products.
Amdt 2
SANS 60079-10/IEC 60079-10, Electrical apparatus for explosive gas atmospheres – Part 10: Classification of hazardous areas.
SANS 60079-11/IEC 60079-11, Electrical apparatus for explosive gas atmosphere – Part 11: Classification of hazardous areas.
Amdt 1
UL 582), Steel underground tanks for flammable and combustible liquids.
Amdt 2
UL 1542), Carbon-dioxide fire extinguishers.
Amdt 2
Regulations for the harbours of the Republic of South Africa (published by Transnet).
South African private siding regulations (published by Transnet).
Transport provision and construction of private sidings (published by Transnet).
© Standards South Africa
2) UL standards are published by Underwriter’s Laboratories Inc., 333 Pfingsten Road, Northbrook, IL 60062-2096 USA (www.ul.com).
Amdt 2
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